Academic literature on the topic 'Mental illness – Complications'

AimsOur objective was to study the psychological morbidity and associated risk factors among antenatal and postnatal patients referred for the psychiatric assessment at University Psychiatry Unit of National Hospital of Sri Lanka.MethodAll the Clinic records of perinatal referrals from 1st January 2019 to 31st December 2019 were assessed. Sociodemographic details, delivery details, health of the newborn, past and present psychiatry illness related details were obtained using a questionnaire. Data were analysed using SPSS.ResultTotal of 161 perinatal referrals were studied. Mean age of the mothers were 28.7 years (SD = 6.60). About 18 (11.8%) were not legally married, partner passed away or estranged. Above Ordinary level education was having 34.5% of participants. Majority were postnatal mothers (61.5%). Some mothers (32.3%) have reported the pregnancy was unexpected whilst 20(32.3%) and 49(30.8%) have experienced delivery complications and neonatal illnesses respectively. Past mental illnesses were found among 31(20.7%) of mothers. Out of whole perinatal referrals maternity blues (28.9%) was the commonest current psychiatry diagnosis. Among antenatal mothers, adjustment disorder (28.8%) and depressive disorder (17.3%) were the commonest. Schizophrenia, Schizophreniform disorder and bipolar illness were found among 8(5%), 6(3.7%) and 3(1.9%) mothers respectively. Major psychoactive substance use disorder was found among 4 (2.5%) mothers. Presence of pregnancy related complications were significantly associated with postpartum metal illnesses(p = 0.008).ConclusionCommonest perinatal mental illness was the maternity blues. Depressive disorder was the commonest major mental illness and neonatal complications were associated with psychological morbidity in postnatal mothers.

Depression, anxiety, posttraumatic stress disorder (PTSD), and substance abuse are linked to higher rates of morbidity and mortality after various surgical procedures. Comparable data in general surgery are lacking. Records from 183 consecutive patients undergoing elective general surgery procedures at a single tertiary hospital were reviewed. Patients with depression, anxiety, PTSD, and substance abuse or any combination of these at the time of surgery were classified as having “active mental illness” (AMI). Thirty-day complications, readmissions, and emergency room (ER) visits were identified. Univariate analysis was performed followed by creation of multivariate regression models. 41.5 per cent (n = 76) met criteria for the AMI group and 58.5 per cent (n = 107) were without a mental illness (WAMI). The two groups had similar incidence of medical comorbidities and similar mean values of serum albumin and creatinine. The AMI group had higher rates of readmissions (14.5 vs 3.7 %, P = 0.009) and ER (19.7 vs 8.4 %, P = 0.025) visits compared with the WAMI group. Differences in length of stay and 30-day complications did not reach statistical significance. In patients undergoing elective general surgery, depression, anxiety, PTSD, and substance abuse are associated with higher rates of readmission and ER visits. These results suggest a need for further research on the impact of specific mental illnesses on postoperative complications.

BackgroundThis exploratory study seeks to generate new hypotheses about the relationship between obstetric complications and schizophrenia.MethodThe British Perinatal Mortality Survey represents 98% of all births during one week in March 1958 in Great Britain. Present State Examination (PSE), Catego diagnoses of narrowly defined schizophrenia (n = 49), broadly defined schizophrenia (n = 79), affective psychosis (n = 44) and neurosis (n = 93) were derived from case notes for all cohort members. The remainder of the cohort, surviving the perinatal period, acted as controls (n = 16 812). Variables in the British Perinatal Mortality Survey were grouped into five categories: the physique/lifestyle of the mother (including demographic characteristics), her obstetric history, the current pregnancy, the delivery and the condition of the baby.ResultsThere were 7/17 significant differences in maternal physique/lifestyle and obstetric history between the births of schizophrenics and controls, compared to 4/40 comparisons of somatic variables relating to pregnancy, birth and the condition of the baby. This compares with 4/17 and 7/40 for affective psychotics and a total of 4/57 differences for all categories of variables when neurotics were contrasted with controls.ConclusionsThe purported increased risk of obstetric complications in schizophrenics may result from the physique/lifestyle of their mothers.

Aims and MethodWe present two patients who developed refeeding syndrome following admission to a general psychiatry ward. The practical implications of assessing and managing medical consequences in patients with mental illness who start refeeding after a period of starvation are discussed.ResultsPatients presented with overlapping clinical manifestations of mental illness and refeeding syndrome that were difficult to recognise and manage.Clinical ImplicationsAwareness of refeeding syndrome in patients with mental illness may prevent fatal physical complications.

(Truncated abstract) The aims of this thesis are: (i) To estimate the prevalence of psychiatric illness among persons with intellectual disability and, conversely, the prevalence of intellectual disability among persons with a psychiatric illness; (ii) To describe the disability and service utilisation profile of persons with conjoint disorder; (iii) To examine, in particular, intellectual disability co-occurring with schizophrenia; and (iv) To explore the role of hereditary and environmental (specifically obstetric) risk factors in the aetiology of (i) intellectual disability and (ii) intellectual disability co-occurring with psychiatric illness. This thesis has a special interest in the relationship between intellectual disability and schizophrenia. Where data and sample sizes permit, it explores that relationship at some depth and has included sections on the putative nature of the link between intellectual disability and schizophrenia in the introductory and discussion chapters. To realise its objectives, the thesis comprises a core study focusing on aims (i) – (iii) and a supplementary study whose focus is aim (iv). It also draws on work from an ancillary study completed prior to the period of candidacy...This thesis found that, overall, 31.7% of persons with an intellectual disability had a psychiatric illness; 1.8% of persons with a psychiatric illness had an intellectual disability. The rate of schizophrenia, but not bipolar disorder or unipolar major depression, was greatly increased among cases of conjoint disorder: depending on birth cohort, 3.7-5.2% of individuals with intellectual disability had co-occurring schizophrenia. Down syndrome was much less prevalent among conjoint disorder cases despite being the most predominant cause of intellectual disability while pervasive developmental disorder was over-represented. Persons with conjoint disorder had a more severe clinical profile including higher mortality rates than those with a single disability. The supplementary study confirmed the findings in the core body of work with respect to the extent of conjoint disorder, its severity, and its relationship with pervasive development disorder and Down syndrome. Moreover, the supplementary study and the ancillary influenza study indicated a role for neurodevelopmental insults including obstetric complications in the adverse neuropsychiatric outcomes, with timing of the insult a potentially critical element in defining the specific outcome. The supplementary study also added new information on familiality in intellectual disability. It found that, in addition to parental intellectual disability status and exposure to labour and delivery complications at birth, parental psychiatric status was an independent predictor of intellectual disability in offspring as well as a predictor of conjoint disorder. In conclusion, the facility to collect and integrate records held by separate State administrative health jurisdictions, and to analyse them within the one database has had a marked impact on the capacity for this thesis to estimate the prevalence of conjoint disorder among intellectually disabled and psychiatric populations, and to understand more about its clinical manifestations and aetiological underpinnings.

Bakgrund: Awareness, oavsiktlig vakenhet, är en ovanlig men allvarlig komplikation vid generell anestesi. Awarenessupplevelsen kan vara traumatisk för patienterna och resultera i långvarig ohälsa. Patienterna har rätt till god vård och anestesisjuksköterskan är ansvarig för att patienterna är adekvat sövda under hela sin anestesi. Syfte: Att belysa patientens upplevelse av awareness under generell anestesi samt vilka konsekvenser det kan resultera i för patienten  Metod: En systematisk integrativ litteraturstudie genomfördes. Litteratursökningar gjordes i databaserna Cinahl, PubMed och PsycINFO. 36 kvalitativa och kvantitativa studier identifierades och analyserades med tematisk syntes. Resultat: Fyra övergripande analytiska teman framkom. Dessa var sensoriska intryck, existentiella känslor, påkalla uppmärksamhet och psykisk ohälsa. De tre första temana berör patientens upplevelse i samband med awareness och det sista temat berör vilka konsekvenser denna upplevelse kunde få för patienterna.  I samband med awareness kunde patienterna uppleva olika sensoriska intryck som hörsel, syn, känsel, smärta och paralys. Dessa upplevelser kunde medföra existentiella känslor som rädsla, oro, ångest, panik och hjälplöshet. Flera patienter beskrev hur de försökte påkalla personalens uppmärksamhet. Upplevelsen av awareness var för en del patienter en traumatisk upplevelse som kunde medföra kortvarig eller långvarig psykisk ohälsa av varierande omfattning. Det kunde även medföra psykosociala konsekvenser med försämrade relationer till närstående och hälso- och sjukvården med följden att patienten ej kunde genomföra rekommenderad behandling. Slutsats: Att uppleva awareness kan innebära ett lidande för patienten. En ökad kunskap om awareness medvetandegör behovet av att förebygga awareness och ökar anestesisjuksköterskans möjlighet att identifiera och stötta patienter som drabbats.
Background: Awareness, (e.g. unintentional wakefullness) is an unusual but serious complication during general anesthesia. The awareness experience can be traumatic for the patients and result in long-term illness. The patients are entitled to good care and the anesthetist nurse is responsible for ensuring that the patients are adequately anesthetized throughout their anesthesia. Aim: The aim was to illustrate the patient’s perception of awareness during general anesthesia and the consequences this may have for the patient.   Method: A systematic integrative literature study was conducted. Literature searches were made in the databases CINAHL, PubMed and PsycINFO. 36 qualitative and quantitative studies were identified and analyzed with thematic synthesis. Result: Four comprehensive analytical themes emerged. These were Sensory impressions, existential feelings, calling for attention and mental illness. The first three themes concern the patient’s experience in relation to awareness and the last theme concerns what consequences this experience could have for the patients. In conjunction with awareness patients could experience different sensory impressions such as hearing, sight, feeling, pain and paralysis. These experiences could cause existential feelings such as fear, anxiety, panic and helplessness. Several patients described how they tried to call on the staff’s attention. The experience of awareness was for some patients a traumatic experience that could cause short-term or longterm psychological sequele of varying degrees. It could also result in psychosocial consequences with deteriorated relationships with both relatives and health care, with the result that the patient could not carry out recommended treatment.  Conclusion: Experiencing awareness may mean a suffering for the patient. An increased knowledge about awareness acknowledges the need to prevent it and increases the ability of the nurse to identify and support patients who are affected.

Syfte: Syftet med studien var att undersöka extra- och intraorala kliniska tecken hos individer med ätstörningen bulimi. Metod: Litteratursökningen har utförts i vetenskapliga databaser; Medline, CINAHL och Dentistry & Oral Sciences Source. Artiklar publicerade mellan år 2000–2021 var inkluderade. Totalt valdes det ut 10 vetenskapliga artiklar för denna litteraturstudie. Resultat: Resultatet visar att de vanligaste kliniska tecknen var reducerat salivflöde, lågt pH-värde i saliven, dentala erosioner, svullnad och erytem i gommens slemhinna, torra och nariga läppar och svullna Glandula Parotis salivkörtlar, dock fanns det ingen statistisk signifikans gällande karies och parodontala sjukdomar. Slutsats: Resultaten visar att intra- och extra kliniska tecken kan ses hos individer med bulimi, framförallt svullna Glandula Parotis salivkörtlar, reducerat salivflöde, lägre pH-värde i saliven och dentala erosioner. Kunskap om extra- och intraorala kliniska tecken hos tandvårdspersonal möjliggör tidig identifiering av sjukdomen bulimi och att preventiva insatser tillgodoses i ett tidigt stadie för att minska lidande hos patienten.
Aim: The aim of this study was to investigate extra- and intraoral clinical signs in individuals with the eating disorder bulimia. Material and method: An advanced search of literature has been completed in data bases as; Medline, CINAHL and Dentistry & Oral sciences source. Articles published in 2000-2021 were included. A total of 10 articles were included in this study. Results: The results show that the most common clinical signs were hyposalivation, low pH in the saliva, dental erosion, swelling and erythema in the palate mucosa, dry lips and swollen Glandula Parotid salivary glands. There were no statistically significant results in caries and periodontal diseases. Conclusions: There are some intra- and extraoral clinical signs that can be seen in individuals with bulimia, above all swollen Glandula Parotid salivary glands, reduced salivary flow, low pH in the saliva and dental erosions. Knowledge in extra- and intraoral clinical signs in dental staff makes it possible for early identification of the disease bulimia and preventive efforts can be offered in an early stage to reduce suffering for the patient.

Thesis (M.Med.(Psychiatry))--University of the Witwatersrand, Faculty of Health Sciences, 2014.
The Luthando Neuropsychiatric HIV clinic was set up at Chris Hani Baragwanath Academic Hospital as an anti-retroviral roll out centre, specifically designed to provide anti-retroviral therapy to HIV positive patients with a psychiatric illness. Adherence to HIV treatment is essential for virological suppression, and non-adherence is a key factor in treatment failure. Research has suggested that psychiatric illness may negatively influence adherence to ART. Importantly, negative perceptions with regards to adherence may affect the decision to initiate ART in psychiatric patients. Attendance at clinic appointments is the first step in adherence, and has been found to be one of the most important predictors of medication adherence. Attendance at first clinic appointment is easily measurable in a limited resource setting, such as South Africa. The aim of this study was to examine the rate of attendance at the first clinic appointment post discharge from psychiatric hospitalization in HIV positive psychiatric patients initiated on ART as in-patients, and to determine which factors, if any may be related to clinic attendance. This study was a retrospective record review, conducted at Chris Hani Baragwanath Academic Hospital, at the Luthando clinic. Patients that were initiated on ART as psychiatric in-patients, 18 years to 65 years of age from 1st July 2009 to 31st December 2010 and then discharged for follow up as out-patients at Luthando clinic were included in the sample. The primary outcome was attendance at the clinic post discharge from hospital. Socioeconomic and clinical data were also recorded and analysed, comparing attendant and non-attendant P a g e | vi groups. The rate of attendance was 79.59%. There were a number of similarities between the attendant and non-attendant patients in terms of demographic and clinical data. The only significant difference between the attendant and non-attendant groups was disclosure of HIV status, and significantly fewer non-attendant patients had disclosed their HIV status to their treatment supporter (p = .01). Further research needs to quantify the significance of in-patient vs. out-patient initiation of ART, as well as to investigate the impact of a psychiatric diagnosis on attendance at ART clinics. Non-disclosure of HIV status needs to be further investigated and addressed in HIV treatment facilities in order to improve attendance.

Background Patients infected with the human immunodeficiency virus (HIV), the causative agent of the acquired immunodeficiency syndrome (AIDS), have high rates of psychiatric morbidity. The effects of HIV on the Central Nervous System may lead to psychiatric morbidity even before the appearance of the full-blown AIDS syndrome. Sero-prevalence studies of patients with psychoses have found an estimated 5-20% to be HIV positive. However, sero-prevalence estimates vary from study to study due to the differences in sampling by geographic location, socio-economic class, race and ethnicity, and psychiatric-diagnostic composition. The Republic of South Africa has some of the highest prevalence rates in the world and research in this field is escalating rapidly. However research on HIV in patients with mental illness, particularly psychosis is very sparse. Aim of the study To determine the prevalence of HIV sero-positivity amongst patients admitted to Town Hill hospital presenting with first episode psychosis. Method All patients presenting to Town Hill hospital with first episode of psychotic symptoms were recruited to participate in the study. The treating doctor in collaboration with the multi-disciplinary team made the diagnosis of Psychosis. A total number of 63 patients participated in the study. Results. 23.8% of the patients tested positive for the human immunodeficiency virus. Conclusions. The prevalence of HIV sero-positivity is high amongst patients presenting with first episode psychosis. The HIV epidemic could have an important effect on the aetiology and clinical presentation of psychosis. Recommendations State mental health authorities should pursue the promotion of voluntary HIV testing programs, in patients presenting with first episode psychosis as soon as they are capable of giving informed consent.
Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2007.

Post-intensive care syndrome is defined as new or worsening impairment in cognition, mental health, or physical function that persists after a critical illness. The complexities of post-intensive care syndrome come from the interactions of the patient’s premorbid mental health and physical function, the acute physiologic derangements and acute organ injury of the critical illness, and the side effects of procedures, treatments, and potential complications incurred during the critical illness. Problems are better described as challenging syndromes rather than specific actionable diagnoses, with the four major functional problems for patients being weakness, cognitive impairment, psychological problems, and new or worsened organ dysfunction. The sequelae of critical illness often extend beyond patients and impact the families of critically ill patients.

Classification is essential in medicine to help doctors acquire, learn, and recall clinically useful information about problems coming to healthcare professionals’ attention. There problems include both essentialist diagnostic constructs (where all examples share a quality and are distinct from other constructs) and nominalist diagnostic constructs (used to describe clinically useful concepts not necessarily separate from other constructs). Diagnostic constructs may be recognized using defined criteria and/or as prototypical examples. They are based on similarities in clinical picture, mechanisms/processes, and/or causes. They may be used to identify clinically important situations, diseases/clear-cut syndromes, spectrums of health, illness(es)/and condition(s), injuries, and other situations of interest to healthcare professionals. Thresholds established on the basis of clinical utility (e.g. level of distress or risk of complications) may be used to define conditions. Care must be taken to guard against over-medicalization of problems or situations.

For persons with HIV and AIDS, a thorough and comprehensive assessment has far-reaching implications not only for compassionate, competent, and coordinated care but also for adherence to medical treatment and risk reduction, as well as public health. Primary physicians, HIV specialists, as well as psychiatrists and other mental health professionals can play an important role in preventing the spread of HIV infection. Psychiatric disorders are associated with inadequate adherence to risk reduction, medical care, and antiretroviral therapy. While adherence to medical care for most medical illnesses has major meaning to patients, loved ones, and families, adherence to medical care for HIV and AIDS has major implications for reduction of HIV transmission and prevention of emergence of drug-resistant HIV viral strains (Cohen and Chao, 2008). Many persons with HIV and AIDS have psychiatric disorders (Stoff et al., 2004) and can benefit from psychiatric consultation and care. The rates of HIV infection are also higher among persons with serious mental illness (Blank et al., 2002), indicating a bidirectional relationship. Some persons with HIV and AIDS have no psychiatric disorder, while others have a multiplicity of complex psychiatric disorders that are responses to illness or treatments or are associated with HIV/AIDS (such as HIV-associated dementia) or multimorbid medical illnesses and treatments (such as hepatitis C, cirrhosis, end-stage liver disease, HIV nephropathy, end-stage renal disease, anemia, coronary artery disease, and cancer). Persons with HIV and AIDS may also have multimorbid psychiatric disorders that are co-occurring and may be unrelated to HIV (such as posttraumatic stress disorder, or PTSD, schizophrenia, and bipolar disorder). The complexity of AIDS psychiatric consultation is illustrated in an article (Freedman et al., 1994) with the title “Depression, HIV Dementia, Delirium, Posttraumatic Stress Disorder (or All of the Above).” Comprehensive psychiatric evaluations can provide diagnoses, inform treatment, and mitigate anguish, distress, depression, anxiety, and substance use in persons with HIV and AIDS. Furthermore, thorough and comprehensive assessment is crucial because HIV has an affinity for brain and neural tissue and can cause central nervous system (CNS) complications even in healthy seropositive individuals. Because of potential CNS complications as well as the multiplicity of other severe and complex medical illnesses in persons with HIV and AIDS (Huang et al., 2006), every person who is referred for a psychiatric consultation needs a full biopsychosocial evaluation.

Physical and mental health problems in older people often co-exist, and may be inter-related. This chapter explores the use of the Comprehensive Geriatric Assessment (CGA) to holistically address the impacts of multiple physical and psychiatric comorbidities on older peoples’ health and function. Older people with mental health problems are particularly vulnerable to frailty and the impacts of polypharmacy. They may present with atypical complaints, are prone to complications, and are at risk of quickly losing their functional abilities. A period of rehabilitation is often necessary to restore functioning after an episode of illness. Multidisciplinary working is essential to offer holistic management of problems commonly seen in older people, including immobility, falls, confusion and incontinence. A focus on person-centred care is particularly important for people living with dementia, and this chapter describes an approach to healthcare that promotes open communication with patients and carers, shared decision-making, and advance care planning.

In this paper, Winnicott argues that psychosis is an illness of a psychological nature, in some cases with a physical basis, which is concerned with the elements of human personality and existence. It is a term that includes schizophrenia, manic depression and melancholia with more or less paranoid complications. Winnicott argues that psychosis represents an organization of defences, and behind all organized defences is the threat of confusion, a breakdown of integration. Winnicott indicates there is acute need for preventive measures, especially in the provision of mental care for children, perhaps in a residential centre where children live indefinitely and could be taken for daily treatment by psycho-analysts. Winnicott proposes that psychosis proper indicates a disturbance of emotional development at an early stage. In some cases a hereditary tendency to psychosis is strong, whereas in others it is not a significant feature.

Hypothermia occurs when the body’s core temperature drops below 35°C (95°F). Symptoms increase as body temperature decreases. Symptoms can include (from mild to severe): shivering, decreased fine motor dexterity, impairment in judgment, gait instability, decreased mental status, and loss of consciousness. Rapid rewarming is critical. A hypothermic patient should not be considered dead until “they are warm and dead.” This chapter highlights a case of profound hypothermia caused by cold water immersion. The chapter details the case, including the history, physical exam, and treatment. Key management points include the assumption of complicating traumatic injury or medical illness until rewarming is complete; active core rewarming; continuous cardiopulmonary resuscitation until goal core temperature is achieved; understanding that prolonged cardiopulmonary resuscitation may be necessary; and the recognition of Osborne J waves on the electrocardiogram.

The World Health Organization has declared that the spread of tuberculosis is a global emergency. Despite the implementation of strong tuberculosis-control initiatives by WHO, this highly infectious disease continues to affect all vulnerable populations, including the elderly population. Adverse social factors and poor living conditions also affect the elderly much more than the young. The clinical characteristics of tuberculosis in older adults can be unusual and may be confused with age-related illnesses. Various factors related to old age can also cause complications in the diagnosis, treatment, and disease outcomes for tuberculosis patients. The contributory factors may be poor memory, deafness, mental confusion, or impairment of speech. In addition, therapy for tuberculosis in elderly individuals is challenging because of the increased incidence of adverse drug reactions. Hence, understanding the impact of these substantial aspects will help to overcome the problem of tuberculosis in the elderly population.

A cohort study is one in which the outcome (usually disease status) is ascertained for groups of individuals defined on the basis of their exposure. At the time exposure status is determined, all must be free of the disease. All eligible participants are then followed up over time. Since exposure status is determined before the occurrence of the outcome, a cohort study can clarify the temporal sequence between exposure and outcome, with minimal information bias. The historical and the population cohort study (Box 9.1) are efficient variants of the classical cohort study described above, which nevertheless retain the essential components of the cohort study design. The exposure can be dichotomous [i.e. exposed (to obstetric complications at birth) vs. not exposed], or graded as degrees of exposure (e.g. no recent life events, one to two life events, three or more life events). The use of grades of exposure strengthens the results of a cohort study by supporting or refuting the hypothesis that the incidence of the disease increases with increasing exposure to the risk factor; a so-called dose–response relationship. The essential features of a cohort study are: ♦ participants are defined by their exposure status rather than by outcome (as in case–control design); ♦ it is a longitudinal design: exposure status must be ascertained before outcome is known. The classical cohort study In a classical cohort study participants are selected for study on the basis of a single exposure of interest. This might be exposure to a relatively rare occupational exposure, such as ionizing radiation (through working in the nuclear power industry). Care must be taken in selecting the unexposed cohort; perhaps those working in similar industries, but without any exposure to radiation. The outcome in this case might be leukaemia. All those in the exposed and unexposed cohorts would need to be free of leukaemia (hence ‘at risk’) on recruitment into the study. The two cohorts would then be followed up for (say) 10 years and rates at which they develop leukaemia compared directly. Classical cohort studies are rare in psychiatric epidemiology. This may be in part because this type of study is especially suited to occupational exposures, which have previously been relatively little studied as causes of mental illness. However, this may change as the high prevalence of mental disorders in the workplace and their negative impact upon productivity are increasingly recognized. The UK Gulf War Study could be taken as one rather unusual example of the genre (Unwin et al. 1999). Health outcomes, including mental health status, were compared between those who were deployed in the Persian Gulf War in 1990–91, those who were later deployed in Bosnia, and an ‘era control group’ who were serving at the time of the Gulf war but were not deployed. There are two main variations on this classical cohort study design: they are popular as they can, depending on circumstances, be more efficient than the classical cohort design. The population cohort study In the classical cohort study, participants are selected on the basis of exposure, and the hypothesis relates to the effect of this single exposure on a health outcome. However, a large cohort or panel of subjects are sometimes recruited and followed up, often over many years, to study multiple exposures and outcomes. No separate comparison group is required as the comparison group is generally an unexposed sub-group of the panel. Examples include the British Doctor's Study in which over 30,000 British doctors were followed up for over 20 years to study the effects of smoking and other exposures on health (Doll et al. 1994), and the Framingham Heart Study, in which residents of a town in Massachusetts, USA have been followed up for 50 years to study risk factors for coronary heart disease (Wolf et al. 1988). The Whitehall and Whitehall II studies in the UK (Fuhrer et al. 1999; Stansfeld et al. 2002) were based again on an occupationally defined cohort, and have led to important findings concerning workplace conditions and both physical and psychiatric morbidity. Birth cohort studies, in which everyone born within a certain chronological interval are recruited, are another example of this type of study. In birth cohorts, participants are commonly followed up at intervals of 5–10 years. Many recent panel studies in the UK and elsewhere have been funded on condition that investigators archive the data for public access, in order that the dataset might be more fully exploited by the wider academic community. Population cohort studies can test multiple hypotheses, and are far more common than any other type of cohort study. The scope of the study can readily be extended to include mental health outcomes. Thus, both the British Doctor's Study (Doll et al. 2000) and the Framingham Heart Study (Seshadri et al. 2002) have gone on to report on aetiological factors for dementia and Alzheimer's Disease as the cohorts passed into the age groups most at risk for these disorders. A variant of the population cohort study is one in which those who are prevalent cases of the outcome of interest at baseline are also followed up effectively as a separate cohort in order (a) to study the natural history of the disorder by estimating its maintenance (or recovery) rate, and (b) studying risk factors for maintenance (non-recovery) over the follow-up period (Prince et al. 1998). Historical cohort studies In the classical cohort study outcome is ascertained prospectively. Thus, new cases are ascertained over a follow-up period, after the exposure status has been determined. However, it is possible to ascertain both outcome and exposure retrospectively. This variant is referred to as a historical cohort study (Fig. 9.1). A good example is the work of David Barker in testing his low birth weight hypothesis (Barker et al. 1990; Hales et al. 1991). Barker hypothesized that risk for midlife vascular and endocrine disorders would be determined to some extent by the ‘programming’ of the hypothalamo-pituitary axis through foetal growth in utero. Thus ‘small for dates’ babies would have higher blood pressure levels in adult life, and greater risk for type II diabetes (through insulin resistance). A prospective cohort study would have recruited participants at birth, when exposure (birth weight) would be recorded. They would then be followed up over four or five decades to examine the effect of birth weight on the development of hypertension and type II diabetes. Barker took the more elegant (and feasible) approach of identifying hospitals in the UK where several decades previously birth records were meticulously recorded. He then traced the babies as adults (where they still lived in the same area) and measured directly their status with respect to outcome. The ‘prospective’ element of such studies is that exposure was recorded well before outcome even though both were ascertained retrospectively with respect to the timing of the study. The historical cohort study has also proved useful in psychiatric epidemiology where it has been used in particular to test the neurodevelopmental hypothesis for schizophrenia (Jones et al. 1994; Isohanni et al. 2001). Jones et al. studied associations between adult-onset schizophrenia and childhood sociodemographic, neurodevelopmental, cognitive, and behavioural factors in the UK 1946 birth cohort; 5362 people born in the week 3–9 March 1946, and followed up intermittently since then. Subsequent onsets of schizophrenia were identified in three ways: (a) routine data: cohort members were linked to the register of the Mental Health Enquiry for England in which mental health service contacts between 1974 and 1986 were recorded; (b) cohort data: hospital and GP contacts (and the reasons for these contacts) were routinely reported at the intermittent resurveys of the cohort; (c) all cohort participants identified as possible cases of schizophrenia were given a detailed clinical interview (Present State examination) at age 36. Milestones of motor development were reached later in cases than in non-cases, particularly walking. Cases also had more speech problems than had noncases. Low educational test scores at ages 8,11, and 15 years were a risk factor. A preference for solitary play at ages 4 and 6 years predicted schizophrenia. A health visitor's rating of the mother as having below average mothering skills and understanding of her child at age 4 years was a predictor of schizophrenia in that child. Jones concluded ‘differences between children destined to develop schizophrenia as adults and the general population were found across a range of developmental domains. As with some other adult illnesses, the origins of schizophrenia may be found in early life’. Jones' findings were largely confirmed in a very similar historical cohort study in Finland (Isohanni et al. 2001); a 31 year follow-up of the 1966 North Finland birth cohort (n = 12,058). Onsets of schizophrenia were ascertained from a national hospital discharge register. The ages at learning to stand, walk and become potty-trained were each related to subsequent incidence of schizophrenia and other psychoses. Earlier milestones reduced, and later milestones increased, the risk in a linear manner. These developmental effects were not seen for non-psychotic outcomes. The findings support hypotheses regarding psychosis as having a developmental dimension with precursors apparent in early life. There are many conveniences to this approach for the contemporary investigator. ♦ The exposure data has already been collected for you. ♦ The follow-up period has already elapsed. ♦ The design maintains the essential feature of the cohort study, namely that information bias with respect to the assessment of the exposure should not be a problem. ♦ As with the Barker hypothesis example, historical cohort studies are particularly useful for investigating associations across the life course, when there is a long latency between hypothesized exposure and outcome. Despite these important advantages, such retrospective studies are often limited by reliance on historical data that was collected routinely for other purposes; often these data will be inaccurate or incomplete. Also information about possible confounders, such as smoking or diet, may be inadequate.