Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Utility of pharmacogenetic testing to optimise antidepressant pharmacotherapy in youth: a narrative literature review

Pharmacogenetics (PGx) is the study and application of how interindividual differences in our genomes can influence drug responses. By evaluating individuals' genetic variability in genes related to drug metabolism, PGx testing has the capabilities to individualise primary care and build a safer drug prescription model than the current "one-size-fits-all" approach. In particular, the use of PGx testing in psychiatry has shown promising evidence in improving drug efficacy as well as reducing toxicity and adverse drug reactions. Despite randomised controlled trials demonstrating an evidence base for its use, there are still numerous barriers impeding its implementation. This review paper will discuss the management of mental health conditions with PGx-guided treatment with a strong focus on youth mental illness. PGx testing in clinical practice, the concerns for its implementation in youth psychiatry, and some of the barriers inhibiting its integration in clinical healthcare will also be discussed. Overall, this paper provides a comprehensive review of the current state of knowledge and application for PGx in psychiatry and summarises the capabilities of genetic information to personalising medicine for the treatment of mental ill-health in youth.

Patient engagement in perioperative settings: A mixed method systematic review

BACKGROUND

Patient engagement has emerged as a key focus in the research literature to facilitate patients' recovery. The term is commonly used by researchers, yet without working definitions. This lack of clarity is further complicated by the interchangeable use of a few terms.

OBJECTIVES

This systematic review aimed at identifying how patient engagement was conceptualised and operationalised in perioperative settings.

METHODS

MEDLINE, EMBASE, CINAHL and the Cochrane Library were searched for publications in English discussing patient engagement during the perioperative phase. Three reviewers conducted study selection and methodological assessment using Joanna Briggs Institute mixed methods review framework. Reflexive thematic analysis was used to analyse qualitative data and descriptive analysis for quantitative data.

FINDINGS

Twenty-nine studies were included with a total sample of 6289. Study types included qualitative (n = 14) and quantitative (n = 15) with different types of surgery. Sample sizes ranged from n = 7 to n = 1315. Only 38% (n = 11) of included studies offered an explicit definition. Four themes associated with operationalisation included provision of information, which was most studied theme, communication, decision-making and action-taking behaviours. All four themes were interconnected and co-dependent on each other.

CONCLUSIONS

Patient engagement in perioperative settings is a complex and multifaceted concept. The conceptual void in the literature calls for more theoretically informed and comprehensive approaches to researching surgical patient engagement. Future research should aim to better understand the factors that influence patient engagement, as well as the impact of different forms of engagement on patient outcomes through the whole surgical journey of a patient.

Controversies in anaesthesia for noncardiac surgery in older adults

As the population of the world is rapidly ageing, the amount of surgery being performed in older patients is also increasing. Special attention is required for the anaesthetic and perioperative management of these patients. The clinical and non-clinical issues specific to older surgical patients are reviewed, with a special emphasis on areas of debate related to anaesthesia care in this group. These issues include the role of frailty and disability in preoperative assessment, choice of anaesthesia technique for hip fracture, postoperative delirium, and approaches to shared decision-making before surgical procedures.

Outcomes after emergency abdominal surgery in patients with advanced cancer: Opportunities to reduce complications and improve palliative care

BACKGROUND

There is increasing emphasis on the appropriateness and quality of acute surgical care for patients with serious illness and at the end of life. However, there is a lack of evidence regarding outcomes after emergent major abdominal surgery among patients with advanced cancer to guide treatment decisions. This analysis sought to characterize adverse outcomes (mortality, complications, institutional discharge) and to identify factors independently associated with 30-day mortality among patients with disseminated cancer who undergo emergent abdominal surgery for intestinal obstruction or perforation.

METHODS

This is a retrospective cohort study of 875 disseminated cancer patients undergoing emergency surgery for perforation (n = 499) or obstruction (n = 376) at hospitals participating in the American College of Surgeons' National Surgical Quality Improvement Program from 2005 to 2012. Predictors of 30-day mortality were identified using multivariate logistic regression.

RESULTS

Among patients who underwent surgery for perforation, 30-day mortality was 34%, 67% had complications, and 52% were discharged to an institution. Renal failure, septic shock, ascites, dyspnea at rest, and dependent functional status were independent preoperative predictors of death at 30 days. When complications were considered, postoperative respiratory complications and age (75-84 years) were also predictors of mortality.Patients who had surgery for obstruction had a 30-day mortality rate of 18% (n = 68), 41% had complications, and 60% were discharged to an institution. Dependent functional status and ascites were independent predictors of death at 30 days. In addition to these predictors, postoperative predictors of mortality included respiratory and cardiac complications. Few patients (4%) had do-not-resuscitate orders before surgery.

CONCLUSION

Emergency abdominal operations in patients with disseminated cancer are highly morbid, and many patients die soon after surgery. High rates of complications and low rates of preexisting do-not-resuscitate orders highlight the need for targeted interventions to reduce complications and integrate palliative approaches into the care of these patients.

LEVEL OF EVIDENCE

Prognostic study, level III; therapeutic study, level IV.

Weight maintenance and relapse in obesity: a qualitative study

OBJECTIVE

To investigate, among women with obesity who have lost weight, the psychological factors associated with successfully maintaining the new lower weight, as opposed to weight regain.

DESIGN

Qualitative research methods (in-depth individual interviews and group interviews) were used to assess the characteristics of successful weight maintainers, as compared with weight regainers and healthy-weight women.

SUBJECTS

In all, 76 females were recruited from the community, comprising 28 formerly obese women who had lost weight and maintained their new lower weight for at least 1 y; 28 obese women who had lost weight but regained the weight that they had lost; and 20 women with a stable weight in the healthy range.

RESULTS

Certain psychological factors were identified which characterised the regainers but not the maintainers. These factors were: failure to achieve weight goals and dissatisfaction with the weight achieved; the tendency to evaluate self-worth in terms of weight and shape; a lack of vigilance with regard to weight control; a dichotomous (black-and-white) thinking style; and the tendency to use eating to regulate mood.

CONCLUSION

The results suggest that psychological factors may provide some explanation as to why many people with obesity regain weight following successful weight loss. The factors identified in this study need to be examined further using prospective designs.

Hybrid laparoscopic flexure takedown and open procedure for rectal resection is associated with significantly shorter length of stay than equivalent open resection

PURPOSE

Laparoscopic-assisted, sphincter-saving resection (largest incision < 7 cm) of the middle and distal rectum is technically very difficult and, with regard to cancers, has not been demonstrated to be oncologically safe. The hypothesis of this retrospective study is that a hybrid operation that combines laparoscopic and open methods would be associated with short-term outcome benefits compared with open surgery results for patients undergoing sphincter-saving proctectomy.

METHODS

A total of 31 hybrid and 25 fully open rectal resection patients were compared in this retrospective review. All patients had splenic flexure takedown and rectal anastomosis. The hybrid approach consisted of laparoscopic splenic flexure takedown (with or without partial rectal mobilization and devascularization) followed by completion of the procedure via infraumbilical midline laparotomy. The indication was neoplasm in 87 percent of hybrid patients and in 68 percent of open patients. The majority of tumors were located between 4 and 10 cm from the dentate line.

RESULTS

Fifty-eight percent of hybrid and 68 percent of open patients had low anterior or coloanal resections, and 48 percent of hybrid and 64 percent of open patients underwent temporary diversion via ileostomy. The mean hybrid midline incision length was 11 cm compared with 24 cm for open patients (P < 0.0001). The neoplastic specimens were similar with regard to margins and lymph node harvest. Similar complication rates were noted in both groups. Nonsignificant benefits for hybrid patients (0.9-1.2 days) were seen with regard to length of time until toleration of liquid or solid diet and first flatus. Hybrid patients experienced their first bowel movements 4.1 days vs. 5.7 days for the open group (P = 0.03). Mean length of stay was significantly shorter for hybrid patients (6.1. days) than for open patients (11.1 days; P = 0.0006).

CONCLUSION

This preliminary retrospective study suggests that a combined hybrid laparoscopic and open approach to sphincter-saving proctectomy permits a similar resection as open methods and may be associated with a length-of-stay benefit and more rapid return of bowel function. Prospective studies will be needed before any firm conclusions can be drawn.

A new cognitive behavioural approach to the treatment of obesity

While behavioural approaches to the management of obesity are often successful in achieving clinically significant weight loss, the weight lost is generally regained. The great majority of patients return to their pre-treatment weight within 3 years. There have been attempts to improve the long-term effectiveness of behavioural treatment but the results have been disappointing. In this paper we suggest that, among other factors, this is because of the neglect of the contribution of cognitive factors to weight regain, and because there is often ambiguity over the goals of treatment. We present a cognitive behavioural analysis of the processes involved in weight regain, and we describe a new cognitive behavioural treatment derived from it. This treatment is designed to minimise the problem of weight regain by addressing psychological obstacles to the acquisition of, and long-term adherence to, effective weight-control behaviour.

The natural course of bulimia nervosa and binge eating disorder in young women

BACKGROUND

Little is known about the relative course and outcome of bulimia nervosa and binge eating disorder.

METHODS

Two community-based cohorts were studied prospectively over a 5-year year period. One comprised 102 participants with bulimia nervosa and the other 48 participants with binge eating disorder (21% [9/42] of whom had comorbid obesity). All participants were female and aged between 16 and 35 years at recruitment. The assessments were at 15-month intervals and addressed eating disorder features, general psychiatric symptoms, and social functioning.

RESULTS

Both cohorts showed marked initial improvement followed by gradual improvement thereafter. Between half and two thirds of the bulimia nervosa cohort had some form of eating disorder of clinical severity at each assessment point, although only a minority continued to meet diagnostic criteria for bulimia nervosa. Each year about a third remitted and a third relapsed. The outcome of the binge eating disorder cohort was better, with the proportion with any form of clinical eating disorder declining to 18% (7 of 40) by the 5-year follow-up. The relapse rate was low among this cohort. There was little movement of participants across the 2 diagnostic categories and few sought treatment. Both groups gained weight, with 39% of the binge eating disorder cohort (14 of 36) meeting criteria for obesity at 5-year follow-up.

CONCLUSIONS

These findings suggest that, among young women in the community, bulimia nervosa and binge eating disorder have a different course and outcome. Whereas the prognosis of those with bulimia nervosa was relatively poor, the great majority of those with binge eating disorder recovered.

Risk factors for anorexia nervosa: three integrated case-control comparisons

BACKGROUND

Many risk factors have been implicated in the development of anorexia nervosa. Little is known about their relative contributions, nor in most cases is it clear whether they are specific to anorexia nervosa or risk factors for all eating disorders or for psychiatric disorder in general.

METHODS

We used a case-control design involving the comparison of 67 female subjects with a history of anorexia nervosa with 204 healthy control subjects, 102 subjects with other psychiatric disorders, and 102 subjects with bulimia nervosa. A broad range of risk factors was assessed by interview.

RESULTS

The subjects with anorexia nervosa and the healthy controls differed in their exposure to most of the putative risk factors. There was no greater exposure to factors that increased the likelihood of dieting, once the influence of other classes of risk factors had been taken into account. Premorbid perfectionism and negative self-evaluation were especially common and more so than among the general psychiatric controls. Parental obesity and an early menarche, together with parental psychiatric disorder, distinguished those with bulimia nervosa from those with anorexia nervosa.

CONCLUSIONS

There appears to be a broad range of risk factors for anorexia nervosa and bulimia nervosa, some of which are shared with other psychiatric disorders. Factors that increase the likelihood of dieting seem to have more important influence as risk factors for bulimia nervosa than anorexia nervosa. Perfectionism and negative self-evaluation appear to be particularly common and characteristic antecedents of both eating disorders.

A cognitive behavioural theory of anorexia nervosa

A cognitive behavioural theory of the maintenance of anorexia nervosa is proposed. It is argued that an extreme need to control eating is the central feature of the disorder, and that in Western societies a tendency to judge self-worth in terms of shape and weight is superimposed on this need for self-control. The theory represents a synthesis and extension of existing accounts. It is 'new', not so much because of its content, but because of its exclusive focus on maintenance, its organisational structure and its level of specification. It is suggested that the theory has important implications for treatment.

Expressed emotion and depression. A longitudinal study

BACKGROUND

Previous studies show that criticism by relatives during acute depressive illness predicts relapse over nine months, but the course of criticism over time and its relation to the course of illness, have not been examined in depressed patients.

METHOD

Thirty-nine depressed patients and their partners, were interviewed separately at three-monthly intervals over about one year. Illness was assessed by Research Diagnostic Criteria and Hamilton Depression Rating Scale. Criticism was measured by the Camberwell Family Interview.

RESULTS

Criticism when patients were most depressed predicted neither remission nor subsequent relapse. Patients who fully recovered, with or without later relapse, had partners who were consistently uncritical, or critical only at presentation. Patients with residual symptoms during remission had more persistently critical partners.

CONCLUSIONS

The nature of the association between criticism and depression could not be unequivocally established, although it appeared likely that continuing criticism was a result of continuing depression. Relatives' understanding of the illness may mediate between levels of criticism and the course of depression.

Life events, social support and marital relationships in the outcome of severe depression

The effects of life events, social support and marital relationships on outcome were examined in a predominantly recurrent in-patient sample of depressives studied longitudinally every 3 months to remission and up to 15 months thereafter. Outcomes examined were length of time to remission, presence of residual symptoms at remission, and subsequent relapse. There were few associations between these outcomes and the social variables. These findings add to other recent evidence that psychosocial factors are relatively unimportant in the subsequent course of severe and recurrent depressions, in contrast to their contribution to onset of such depressions and subsequent outcome of milder depressions.

Remission and relapse in major depression: a two-year prospective follow-up study

This paper reports the course with respect to remission and relapse of a cohort of predominantly in-patient RDC major depressive subjects, who were followed at 3-monthly intervals to remission and for up to 15 months thereafter. Remission was comparatively rapid with 70% of subjects remitting within 6 months. Only 6% failed to do so by 15 months. However, 40% relapsed over the subsequent 15 months, with all the relapses occurring in the first 10 months. Greater severity of the depression and longer duration of the illness predicted a longer time to remission. Greater initial severity of depression also predicted relapse. Subjects with a worse outcome had not received less adequate treatment than the remainder. Our results confirm the comparatively poor outcome subsequent to remission that has been reported in recent literature, in spite of the availability of modern methods of treatment. The clustering of relapses in the first 10 months gives some support to the distinction between relapse and later recurrence.

Residual symptoms after partial remission: an important outcome in depression

This paper draws attention to an important adverse outcome in depression, the occurrence of residual symptoms after partial remission. Among patients with definite major depression followed every 3 months to remission and thereafter, residual symptoms reaching 8 or more on the Hamilton Depression Scale 17-item total were present in 32% (19) of the 60 who remitted below major depression by 15 months. The pattern was of mild but typical depressive symptoms. Residual symptoms were more common in subjects with more severe initial illness, but were not related to any other predictors, including longer prior illness, dysthymia, or lower dose of drug treatment during the illness episode. There were weak associations with personality that might have been consequences of symptom presence. Residual symptoms were very strong predictors of subsequent early relapse, which occurred in 76% (13/17) of those with residual symptoms and 25% (10/40) of those without.

Depressive thinking: shifts in construct accessibility or in schematic mental models?

Alternative explanations for depression-related changes in thinking were examined. Forty-one depressed patients and 40 controls completed sentence stems involving social approval or personal achievement such as "If I could always be right then others would __ me." The view that depressive thinking primarily reflects a generalized increase in accessibility of negative constructs predicts patients will give more negative completions (e.g., "dislike"). Alternatively, depression could affect the interrelationships between constructs: Use in depression of schematic mental models implying closer dependence of personal worth--acceptance on success--approval predicts patients may give more positive completions (e.g., "like"). Results supported the latter prediction and suggest that depressive thinking reflects changes in high-level mental models used to interpret experience.

Depressive thinking: shifts in construct accessibility or in schematic mental models?

Alternative explanations for depression-related changes in thinking were examined. Forty-one depressed patients and 40 controls completed sentence stems involving social approval or personal achievement such as "If I could always be right then others would __ me." The view that depressive thinking primarily reflects a generalized increase in accessibility of negative constructs predicts patients will give more negative completions (e.g., "dislike"). Alternatively, depression could affect the interrelationships between constructs: Use in depression of schematic mental models implying closer dependence of personal worth--acceptance on success--approval predicts patients may give more positive completions (e.g., "like"). Results supported the latter prediction and suggest that depressive thinking reflects changes in high-level mental models used to interpret experience.

The validity of the eating disorder examination and its subscales

The EDE is a semistructured interview which has been developed as a measure of the specific psychopathology of anorexia nervosa and bulimia nervosa. To establish its discriminant validity it was administered to 100 patients with anorexia nervosa or bulimia nervosa and to 42 controls. The two groups differed significantly on all items. Five subscales were derived on rational grounds and evaluated on the two populations. The alpha coefficients for each subscale indicated a satisfactory degree of internal consistency. The EDE provides clinicians and research workers with a detailed and comprehensive profile of the psychopathological features of patients with eating disorders.

The effects of depression on structural aspects of the recall of prose

Investigated depressed patients' memory for stories. This indicated that although normal Ss showed particularly good recall for units central to the structure of the story, this did not hold for depressed Ss. In contrast, effects of centrality were comparable in high- and low-IQ Ss and effects of imageability of story units were comparable in both depressed and normal Ss. These results are consistent with the hypothesis that depressed patients do not use structure to organize stories when encoding them. A failure to identify central aspects of material and selectively recall them is likely to be a handicap to everyday functioning.

The effects of depression on structural aspects of the recall of prose

Investigated depressed patients' memory for stories. This indicated that although normal Ss showed particularly good recall for units central to the structure of the story, this did not hold for depressed Ss. In contrast, effects of centrality were comparable in high- and low-IQ Ss and effects of imageability of story units were comparable in both depressed and normal Ss. These results are consistent with the hypothesis that depressed patients do not use structure to organize stories when encoding them. A failure to identify central aspects of material and selectively recall them is likely to be a handicap to everyday functioning.

The specificity of the Eating Disorder Inventory

A self-report measure, the Eating Disorder Inventory (EDI), has recently been published. An examination of the responses on the EDI of a sample of psychiatric out-patients who did not have eating problems revealed that many of its subscales may be non-specific in character reflecting the general level of psychological disturbance.

A note on explanation and understanding in psychology

Hetherington has recently argued that psychology's concern with anecdotal evidence, introspective data and rare or one-off events renders the methodology and explanatory model of the natural sciences inappropriate and inadequate; and as such psychology needs to develop its own methods of inquiry. However, an examination of his arguments reveals that psychological data do not require explanation of a radically different kind from that employed in the natural sciences. Hetherington is correct in emphasizing that what is distinctive about the subject matter of psychology is its concern with intentional content; however, the conclusions he draws about the special nature of psychological explanation are unwarranted.

IgM detection by ELISA in the diagnosis of cytomegalovirus infections in homosexual and heterosexual immunosuppressed patients

A new commercially developed cytomegalovirus (CMV)-IgM ELISA was found to be sensitive and specific when compared with sucrose gradient fractionation of Ig classes in CMV antibody-positive and negative sera. The presence of CMV IgM in patients' sera correlated with positive virus isolation from circulating mononuclear blood cells and urine. Serial examinations of patients with primary or recent CMV infection revealed a typical sequence of IgM and IgG development. The frequency of CMV isolation declined as the concentration of IgM decreased and the IgG levels increased. Since the isolation of CMV from clinical specimens is a cumbersome procedure, we suggest that the IgM ELISA could provide rapid and valuable information on the presence of an active or reactivated CMV infection.