Intake of polyunsaturated fatty acids and vitamin E reduces the risk of developing amyotrophic lateral sclerosis.

BACKGROUND: To assess whether the premorbid dietary intake of fatty acids, cholesterol, glutamate or antioxidants was associated with the risk of developing amyotrophic lateral sclerosis (ALS). METHODS: Patients referred to our clinic during 2001-2002, who had definite, probable or possible ALS according to El Escorial criteria, without a familial history of ALS, were asked to participate in a case-control study (132 patients and 220 healthy controls). A food-frequency questionnaire was used to assess dietary intake for the nutrients of interest. Multivariate logistic regression analysis was performed with adjustment for confounding factors (sex, age, level of education, energy intake, body mass index and smoking). RESULTS: A high intake of polyunsaturated fatty acid (PUFA) and vitamin E was significantly associated with a reduced risk of developing ALS (PUFA: odds ratio (OR) = 0.4, 95% confidence interval (CI) = 0.2 to 0.7, p = 0.001; vitamin E: OR = 0.4, 95% CI = 0.2 to 0.7, p = 0.001). PUFA and vitamin E appeared to act synergistically, because in a combined analysis the trend OR for vitamin E was further reduced from 0.67 to 0.37 (p = 0.02), and that for PUFA from 0.60 to 0.26 (p = 0.005), with a significant interaction term (p = 0.03). The intake of flavonols, lycopene, vitamin C, vitamin B2, glutamate, calcium or phytoestrogens was not associated with the risk of developing ALS. CONCLUSION: A high intake of PUFAs and vitamin E is associated with a 50-60% decreased risk of developing ALS, and these nutrients appear to act synergistically.

Coffee consumption is inversely associated with cognitive decline in elderly European men: the FINE Study.

OBJECTIVE: To investigate whether coffee consumption is associated with 10-year cognitive decline in elderly men, as results of previous studies obtained hitherto have been controversial and prospective information on this association has been lacking. DESIGN, SUBJECTS AND SETTING: Six hundred and seventy six healthy men born between 1900 and 1920 from Finland, Italy and the Netherlands participated in a 10-year prospective cohort study. Cognitive functioning was assessed using the Mini-Mental State Examination (0-30 points, with a higher score indicating better cognitive performance). Coffee consumption was estimated in cups per day. A mixed longitudinal model was used to investigate the association between baseline coffee consumption and 10-year cognitive decline. Multiple adjustments were made. RESULTS: Men who consumed coffee had a 10-year cognitive decline of 1.2 points (4%). Non-consumers had an additional decline of 1.4 points (P<0.001). An inverse and J-shaped association was observed between the number of cups of coffee consumed and cognitive decline, with the least cognitive decline for three cups of coffee per day (0.6 points). This decline was 4.3 times smaller than the decline of non-consumers (P<0.001). CONCLUSIONS: Findings suggest that consuming coffee reduces cognitive decline in elderly men. An inverse and J-shaped association may exist between the number of cups of coffee consumed and cognitive decline, with the least cognitive decline for men consuming three cups of coffee per day.

Axon loss is an important determinant of weakness in multifocal motor neuropathy.

BACKGROUND: Multifocal motor neuropathy (MMN) is characterised by asymmetrical weakness and muscle atrophy, in the arms more than the legs, without sensory loss. Despite a beneficial response to treatment with intravenous immunoglobulins (IVIg), weakness is slowly progressive. Histopathological studies in MMN revealed features of demyelination and axon loss. It is unknown to what extent demyelination and axon loss contribute to weakness. Unlike demyelination, axon loss has not been studied systematically in MMN. Aims/ METHODS: To assess the independent determinants of weakness in MMN, 20 patients with MMN on IVIg treatment were investigated. Using a standardised examination in each patient, muscle strength was determined in 10 muscles. In the innervating nerve of each muscle, axon loss was assessed by concentric needle electromyography, and conduction block or demyelinative slowing by motor nerve conduction studies. Multivariate analysis was used to assess independent determinants of weakness. RESULTS: Needle electromyography abnormalities compatible with axon loss were found in 61% of all muscles. Axon loss, and not conduction block or demyelinative slowing, was the most significant independent determinant of weakness in corresponding muscles. Furthermore, axon loss and conduction block were independently associated with each other. CONCLUSION: Axon loss occurs frequently in MMN and pathogenic mechanisms leading to axonal degeneration may play an important role in the outcome of the neurological deficit in patients with MMN. Therapeutic strategies aimed at prevention and reduction of axon loss, such as early initiation of treatment or additional (neuroprotective) agents, should be considered in the treatment of patients with MMN.

Criteria for demyelination based on the maximum slowing due to axonal degeneration, determined after warming in water at 37 degrees C: diagnostic yield in chronic inflammatory demyelinating polyneuropathy.

The diagnosis of chronic inflammatory demyelinating polyneuropathy (CIDP) is based on clinical and laboratory results and on features of demyelination found in nerve conduction studies. The criteria that are currently used to reveal demyelinative slowing in CIDP have several limitations. These criteria were only determined in lower arm and lower leg nerve segments, were not defined with respect to nerve temperature, and the relationship with distal compound muscle action potential (CMAP) amplitudes is unclear. The aim of our study was to determine criteria for demyelinative slowing for lower arm and leg segments as well as for upper arm and shoulder segments at a temperature of 37 degrees C, and to assess whether criteria have to be modified when the distal CMAP is decreased. Included were 73 patients with lower motor neuron disease (LMND), 45 patients with CIDP and 36 healthy controls. The arms and legs were warmed in water at 37 degrees C for at least 30 min prior to an investigation and thereafter kept warm with infrared heaters. The proposed criteria for demyelinative slowing were based on the maximum conduction slowing that may occur as a consequence of axonal degeneration and consisted of the upper boundary (99%) or the lower boundary (1%) of conduction values in LMND. In LMND, the maximum conduction slowing was different for arm and leg nerves and for segments within the arm nerves. Moreover, distal motor latency and motor conduction velocity were slower in nerves with distal CMAP amplitudes below 1 mV than in nerves with distal CMAP amplitudes above 1 mV. For these reasons, separate criteria were proposed for arm nerves, for leg nerves and for different segments within arm nerves, and more stringent criteria were proposed for distal motor latency and motor conduction velocity when the distal CMAP amplitude was below 1 mV. The diagnostic yield in CIDP was assessed using the nerve, and not the patient, as the unit of measurement. Thus, whether demyelinative slowing was present was determined for each nerve. Compared with other criteria, our criteria increased the specificity without affecting sensitivity. We conclude that the present criteria, based on the maximum slowing that may occur as a result of axonal degeneration, allow more accurate detection of demyelinative slowing in CIDP compared with other criteria. It should be emphasized that the proposed criteria can only be applied if the method of warming in water at 37 degrees C for at least 30 min is adopted.

Metabolic cardiovascular syndrome and risk of dementia in Japanese-American elderly men. The Honolulu-Asia aging study.

Cardiovascular risk factors often cluster into a metabolic syndrome that may increase the risk of dementia. The objective of the present study was to assess the long-term association between clustered metabolic cardiovascular risk factors measured at middle age and the risk of dementia in old age. This prospective cohort study of cardiovascular disease was started in 1965 and was extended to a study of dementia in 1991. The subjects were Japanese-American men with an average age of 52.7+/-4.7 (mean+/-SD) years at baseline. Dementia was diagnosed in 215 men, according to international criteria, and was based on a clinical examination, neuropsychological testing, and an informant interview. The z scores were calculated for 7 risk factors (random postload glucose, diastolic and systolic blood pressures, body mass index, subscapular skinfold thickness, random triglycerides, and total cholesterol). The relative risk (RR [95% CI]) of dementia (subtypes) per 1 SD increase in the sum of the z scores was assessed after adjustment for age, education, occupation, alcohol consumption, cigarette smoking, and years of childhood lived in Japan. The z-score sum was higher in demented subjects than in nondemented subjects, indicating a higher risk factor burden (0.74 versus -0.06, respectively; P=0. 008). Per SD increase in the z-score sum, the risk of dementia was increased by 5% (RR 1.05, 95% CI 1.02 to 1.09). The z-score sum was specifically associated with vascular dementia (RR 1.11, 95% CI 1.05 to 1.18) but not with Alzheimer's disease (RR 1.00, 95% CI 0.94 to 1.05). Clustering of metabolic cardiovascular risk factors increases the risk of dementia (mainly, dementia of vascular origin).

A prospective study on circulating insulin-like growth factor I (IGF-I), IGF-binding proteins, and cognitive function in the elderly.

The objective of this study was to investigate the longitudinal relation between the insulin-like growth factor I (IGF-I)/IGF-binding protein (IGFBP) system and cognitive function. The study population consisted of a sample of 186 healthy participants from the population-based Rotterdam Study, aged 55-80 yr. At baseline, we determined fasting blood levels of free and total IGF-I, IGFBP-1, and IGFBP-3. The 30-point Mini-Mental State Examination (MMSE) was used to assess cognitive impairment at baseline (MMSE score of <26; 6% of the sample) and cognitive decline after, on the average, 1.9 yr of follow-up (drop in MMSE score of >1 point/year; 22% of the sample). Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using logistic regression, with adjustment for age, sex, education, body mass index, and fasting insulin levels. Total IGF-I appeared to be inversely related to cognitive impairment, although not significantly. Higher total IGF-I and the total IGF-I/IGFBP-3 ratio were associated with less cognitive decline (OR per SD increase = 0.65; 95% CI = 0.44-0.95 and OR = 0.59; 95% CI = 0.39-0.87, respectively). No relation was observed between free IGF-I and cognitive decline (OR = 0.99; 95% CI = 0.68-1.44). In conclusion, in this prospective study higher serum total IGF-I levels and higher total IGF-I/IGFBP-3 ratios, but not higher free IGF-I levels, were associated with less cognitive decline over the following 2 yr. Circulating total IGF-I levels may reflect an underlying biological process that influences cognitive decline.

A prospective study on cortisol, dehydroepiandrosterone sulfate, and cognitive function in the elderly.

The objective of this study was to investigate the relation between the peripheral concentrations of the adrenal steroid hormones cortisol and dehydroepiandrosterone sulfate (DHEAS) and cognitive impairment and decline. A prospective study design was used. The setting was a suburb of Rotterdam, The Netherlands. The study population consisted of a sample of 189 healthy participants from the population-based Rotterdam Study, aged 55-80 yr, who were invited for an additional examination. Follow-up examinations took place 1.9 yr after baseline, on the average. We determined fasting blood levels of DHEAS before dexamethasone administration and of cortisol and corticosteroid-binding globulin before and after the administration of 1 mg dexamethasone overnight. The 30-point Mini-Mental State Examination (MMSE) was used to assess cognition. The associations with cognitive impairment (MMSE score of <26; 6% of the sample) and cognitive decline (drop in MMSE score of >1 point/yr; 24%) were estimated using logistic regression, with adjustment for age, sex, education, and depressive symptoms. An increase of 1 SD in the estimate of free cortisol (SD = 30.3) was associated with cognitive impairment, although not significantly [odds ratio (OR) = 1.5; 95% confidence interval (CI), 0.9-2.4]. A 1 SD increase in the natural logarithm of cortisol after the administration of 1 mg dexamethasone (SD = 0.68) was associated with an OR for cognitive decline of 1.5 (95% CI, 1.0-2.3). A 1 SD increase in DHEAS (SD = 2.10 micromol/L) was inversely, but nonsignificantly, related to cognitive impairment (OR = 0.5; 95% CI, 0.2-1.1) and cognitive decline (OR = 0.6; 95% CI, 0.4-1.1). The ratio of free cortisol over DHEAS was significantly related to cognitive impairment (OR = 1.8; 95% CI, 1.0-3.2). This prospective study among healthy elderly subjects suggested that basal free cortisol levels were positively related to cognitive impairment, and cortisol levels after dexamethasone treatment were related to cognitive decline. There was an inverse, but nonsignificant, association between DHEAS and cognitive impairment and decline.

Risk estimates of dementia by apolipoprotein E genotypes from a population-based incidence study: the Rotterdam Study.

OBJECTIVES: To provide risk estimates of dementia and Alzheimer disease as a function of the apolipoprotein E (APOE) genotypes and to assess the proportion of dementia that is attributable to the APOE genotypes. DESIGN: Case-control study nested in a population-based cohort study with a mean (SD) follow-up of 2.1 (0.9) years. SETTING: General population in Rotterdam, the Netherlands. PARTICIPANTS: A total of 134 patients with incident dementia and a random sample of 997 nondemented control subjects. No participant had dementia at baseline. MAIN OUTCOME MEASURES: Odds ratios for dementia and Alzheimer disease, the fraction of dementia attributable to the APOE epsilon4 allele, and the proportion of the variance in age at the onset of dementia explained by the APOE genotypes. RESULTS: Persons with the epsilon4/4 genotype had a more than 10-fold higher risk of dementia (odds ratio, 11.2; 95% confidence interval, 3.6-35.2), and subjects with the epsilon3/4 genotype had a 1.7-fold increased risk of dementia (95% confidence interval, 1.0-2.9) as compared with persons with the epsilon3/3 genotype. The proportion of patients with dementia that is attributable to the epsilon4 allele was estimated to be 20%. The APOE genotypes explained up to 10% of the variance in age at the onset of dementia. The association between the epsilon4 allele and dementia was strongest in the youngest age category and in those with a family history of dementia. CONCLUSIONS: The APOE genotype is an important determinant of the risk of dementia. At a population level, however, other factors than the APOE genotype may play an important role in the cause of dementia.

Head trauma and risk of dementia and Alzheimer's disease: The Rotterdam Study.

OBJECTIVE: To investigate the relation between head trauma and incidence of dementia in a prospective population-based study. BACKGROUND: Whether head trauma increases the risk of dementia and AD remains controversial. It has been suggested that the risk might be particularly increased for carriers of the APOE-epsilon4 allele. METHODS: The study population included 6645 participants of the prospective population-based Rotterdam Study, aged 55 years or older, who were free of dementia at baseline. Head trauma with loss of consciousness was measured at baseline by a self-report to a physician and detailed the number of head traumas, time since head trauma, and duration of loss of consciousness. The cohort was followed for incident dementia that was diagnosed according to international criteria. Logistic regression was used to calculate the risk of dementia after adjusting for age, gender, and education. RESULTS: No increased risk of dementia or AD was found for persons with a history of head trauma with loss of consciousness (relative risk [RR] for dementia = 1.0, 95% CI, 0.5-2.0; RR for AD = 0.8, 95% CI, 0.4-1.9). Multiple head traumas, time since head trauma, and duration of unconsciousness did not significantly influence the risk of dementia. In addition, the APOE-epsilon4 allele did not modify the relationship. CONCLUSIONS: This study suggests that mild head trauma is not a major risk factor for dementia or AD in the elderly. In addition, this study does not concur with previous cross-sectional studies suggesting an interaction with the APOE genotype.

Anti-oxidants and cognitive function: a review of clinical and epidemiologic studies.

While the role of diet in heart disease and cancer has received much attention, a possible role for diet in the development of cognitive impairment and dementia is just now being investigated. In this presentation, the putative mechanisms through which anti-oxidants could modulate cellular life in the brain will be briefly discussed. Epidemiologic studies that describe the relation of selected dietary nutrients to cognitive impairment and dementia will be reviewed. In particular, recent results from the analyses of community based follow-up studies, including the Rotterdam Study and the Zutphen Study will be presented. Briefly, these studies provide a mixed picture concerning the relation of anti-oxidants to cognitive impairment or dementia.

Fatty acid intake and the risk of dementia and cognitive decline: a review of clinical and epidemiological studies.

Dietary intake of fatty acids may be related to dementia and cognitive function through a number of plausible mechanisms, such as atherosclerosis and thrombosis, inflammation, via an effect on brain development and membrane functioning, or via accumulation of beta-amyloid. This review gives an overview of the few studies that have investigated the relationship between fatty acid intake (including the fatty acids from fish) and cognitive function or dementia and summarises the results from two Dutch population-based prospective studies: the Zutphen Elderly Study (n=476) and the Rotterdam Study (n=5,386). Additionally, limitations on dietary intake studies are discussed and possible mechanisms behind the investigated associations. Data from the Rotterdam Study showed that high intakes of the following nutrients were associated with an increased risk of dementia after adjustment for confounders: total fat (RR=2.4 (95%CI: 1.1-5.2)), saturated fat (RR=1.9 (95%CI: 0.9-4.0)), and cholesterol (RR=1.7 (95%CI: 0.9-3.2)). A high fish consumption, an important source of n-3 PUFAs, reduced the risk of dementia (RR=0.4 (95%CI: 0.2-0.9)). In the Zutphen Elderly Study a high linoleic acid intake was associated with cognitive impairment (OR=1.8 (95%CI: 1.0-3.0)). A high fish consumption tended to be inversely associated with cognitive impairment and decline (RR=0.5, 95%CI: 0.2-1.2). Since diet is a risk factor that is suitable for intervention these results are hopeful and potentially very important.

Autonomic function in patients with hereditary motor and sensory neuropathy type I and Lambert-Eaton myasthenic syndrome.

Noninvasive tests of four autonomic organ systems (vasomotor control, baroreceptor reflexes, sudomotor function and pupillary reflexes) were performed on nine patients with hereditary motor and sensory neuropathy (HMSN) type I and three patients with Lambert-Eaton myasthenic syndrome (LEMS). The results were compared with those of 33 control subjects. Autonomic dysfunction was considered present when at least two of the four organ system tests were abnormal. The three patients with LEMS had abnormal results in two or more different systems, whereas only one of the nine patients with HMSN type I had two abnormal test results. This study demonstrates that autonomic dysfunction is not a common finding in patients with HMSN type I and its presence should alert us to find the cause of this autonomic disorder.

Apolipoprotein e4 allele and cognitive decline in elderly men.

OBJECTIVES: To determine whether polymorphism of apolipoprotein E--notably, the e4 allele--predicts cognitive deterioration in the general population. DESIGN: Population based cohort investigated in 1990 and in 1993. SETTING: Zutphen, the Netherlands. SUBJECTS: Representative cohort of 538 Dutch men aged 70-89 at baseline. MAIN OUTCOME MEASURES: Cognitive function assessed by mini mental state examination, change in cognitive function and incidence of impaired cognitive function at three years. RESULTS: The baseline prevalence of impaired cognitive function (mini mental state examination score < or = 25) was higher among carriers of the e4 allele compared with men without the allele (41.0% (55) v 31.1% (122) P = 0.03), and this result was still valid after adjustment for age, occupation, smoking, alcohol use, and cardiovascular diseases. The decline in cognitive function at three years was largest in men homozygous for e4 (-2.4 points), intermediate in those heterozygous for e4 (-0.7 points), and lowest in men without e4 (-0.1 points), and it was independent of other risk factors (P = 0.02). The risk of developing impaired cognitive function during follow up was significantly increased in allele carriers compared with non-carriers (27.6% (16/58) v 15.5% (32/207)). The adjusted odds ratio was 2.87 (95% confidence interval 1.29 to 6.42). Twenty two per cent of the risk of developing impaired cognitive function in this population may be attributable to the e4 allele. CONCLUSIONS: The apolipoprotein e4 allele predisposes to cognitive decline in a general population of elderly men.

[Percutaneous vertebroplasty in the treatment of osteoporotic vertebral compression fractures: review of the literature]. / Percutane vertebroplastiek bij de behandeling van osteoporotische wervelinzakkingsfracturen; literatuuronderzoek.

OBJECTIVE: To determine the effectiveness and safety of percutaneous vertebroplasty for the treatment of osteoporotic vertebral compression fractures as published in the scientific literature. DESIGN: Literature review. METHOD: Medline and the Cochrane library were searched with the terms 'percutaneous vertebroplasty', 'vertebral compression fractures', 'osteoporotic' and 'osteoporosis'. Criteria for inclusion were: (a) the studies had to have been published in the period January 1985-August 2002, (b) the study population had to include at least 10 patients, (c) the patients had to have been treated with percutaneous vertebroplasty, and (d) the diagnosis had to have been 'osteoporotic vertebral compression fracture'. RESULTS: Twelve studies met the inclusion criteria. Pain relief was seen in 60%-100% of the patients within the first 24 hours and this result improved to 78-100% in the long term (maximum 4 years). The complications immediately after the procedure were related to cement leakages and were mostly of no clinical consequence. Serious complications such as pulmonary embolism were rare. In the long term, percutaneous vertebroplasty was associated with an increased risk of fractures in the adjacent vertebrae. CONCLUSION: Percutaneous vertebroplasty seems to be effective and safe in the treatment of osteoporotic vertebral compression fractures. A prospective randomised intervention study has, however, not yet been performed. For the time being, percutaneous vertebroplasty should be reserved for carefully selected patients in whom conservative therapy has not produced results.

Decline in cognitive functioning is associated with a higher mortality risk.

OBJECTIVE: This study investigates the association between 5-year change in cognitive functioning and subsequent mortality. METHODS: Four hundred and ninety-three Dutch and Italian men from the Finland, Italy, and the Netherlands Elderly (FINE) Study, born between 1900 and 1920, participated in the present study between 1990 and 2000. Cognitive functioning was measured with the Mini-Mental State Examination in 1990 and 1995, and mortality data were obtained until the year 2000. A proportional hazard analysis was used to investigate the association between 5-year change in cognitive functioning and subsequent 5-year mortality. Adjustments were made for age, education, country, lifestyle factors, prevalence of chronic diseases and, additionally, for baseline cognitive functioning. RESULTS: Men whose cognition decreased (more than 1 standard deviation) between 1990 and 1995 had a 2-fold higher risk of dying in the following 5 years compared with men whose cognition was stable (adjusted hazard ratio=1.9; 95% confidence interval 1.3-2.7). Mortality risk of men whose cognition improved between 1995 and 2000 was not different from men whose cognition was stable (adjusted hazard ratio=1.1, 95% confidence interval 0.7-1.9). CONCLUSION: A decline in cognitive functioning is associated with a higher mortality risk.

Feasibility and cost efficiency of a diagnostic guideline for chronic polyneuropathy: a prospective implementation study.

BACKGROUND: Extensive investigations are often performed to reveal the cause of chronic polyneuropathy. It is not known whether a restrictive diagnostic guideline improves cost efficiency without loss of diagnostic reliability. METHODS: In a prospective multicentre study, a comparison was made between the workup in patients with chronic polyneuropathy before and after guideline implementation. RESULTS: Three hundred and ten patients were included: 173 before and 137 after guideline implementation. In all patients, the diagnosis would remain the same if the workup was limited to the investigations in the guideline. After guideline implementation, the time to reach a diagnosis decreased by two weeks. There was a reduction of 33% in the number and costs of routine laboratory investigations/patient, and a reduction of 27% in the total number of laboratory tests/patient, despite low guideline adherence. CONCLUSION: The implementation of a diagnostic guideline for chronic polyneuropathy can reduce diagnostic delay and the number and costs of investigations for each patient without loss of diagnostic reliability. Continuous evaluation strategies after guideline implementation may improve guideline adherence and cost efficiency.

Chest radiography and pneumonia in primary care: diagnostic yield and consequences for patient management.

The current prospective cohort study assessed the diagnostic yield of chest radiography (CXR) in primary-care patients suspected of pneumonia. In total, 192 patients with a clinical suspicion of pneumonia aged >/=18 yrs were referred by their general practitioner (GP) for CXR to one of the three participating hospitals in the Netherlands. All GPs were asked to complete a standardised form before and after CXR. Pneumonia was diagnosed by GPs in 35 (18%) patients, of whom 27 (14%) patients had a positive CXR, and eight (4%) patients a negative CXR, but with an assumed high probability of pneumonia by the GP. CXR clearly influenced the diagnosis of pneumonia by the GP in 53% of the patients. CXR ruled out pneumonia in 47% and the probability of pneumonia substantially increased in 6% of the patients. Patient management changed after CXR in 69% of the patients, mainly caused by a reduction in medication prescription (from 43 to 17%) and more frequent reassurance of the patient (from 8 to 35%). In conclusion, pneumonia was frequently over diagnosed clinically by general practitioners. Chest radiography is a valuable diagnostic tool to substantially reduce the number of patients misdiagnosed and is particularly important for the exclusion of pneumonia in general practice.

Long-term outcome in polymyositis and dermatomyositis.

BACKGROUND: Although polymyositis and dermatomyositis are regarded as treatable disorders, prognosis is not well known, as in the literature long-term outcome and prognostic factors vary widely. AIM: To analyse the prognostic outcome factors in polymyositis and adult dermatomyositis. METHODS: We determined mortality, clinical outcome (muscle strength, disability, persistent use of drugs and quality of life) and disease course and analysed prognostic outcome factors. RESULTS: Disease-related death occurred in at least 10% of the patients, mainly because of associated cancer and pulmonary complications. Re-examination of 110 patients after a median follow-up of 5 years showed that 20% remained in remission and were off drugs, whereas 80% had a polycyclic or chronic continuous course. The cumulative risk of incident connective tissue disorder in patients with myositis was significantly increased. 65% of the patients had normal strength at follow-up, 34% had no or slight disability, and 16% had normal physical sickness impact profile scores. Muscle weakness was associated with higher age (odds ratio (OR) 3.6; 95% confidence interval (CI) 1.3 to 10.3). Disability was associated with male sex (OR 3.1; 95% CI 1.2 to 7.9). 41% of the patients with a favourable clinical outcome were still using drugs. Jo-1 antibodies predicted the persistent use of drugs (OR 4.4, 95% CI 1.3 to 15.0). CONCLUSIONS: Dermatomyositis and polymyositis are serious diseases with a disease-related mortality of at least 10%. In the long term, myositis has a major effect on perceived disability and quality of life, despite the regained muscle strength.