MIDLIFE CARDIOVASCULAR RISK FACTORS ALSO RAISE RISK OF DEMENTIA

The presence of cardiovascular risk factors at midlife increases the risk of late-life dementia, according to Rachel A. Whitmer, PhD, of Kaiser Permanente Division of Research in Oakland, California, and colleagues. They found that high cholesterol levels, hypertension, diabetes, and smoking at midlife were each associated with a 20% to 40% increase in risk of dementia. Additionally, risk of dementia increased even further when multiple risk factors were present. Detailed results of the study were published in the January 25 Neurology.

A total of 8,845 participants age 40 to 44 underwent health evaluations from 1964 to 1973. The researchers found that at midlife, 11% of participants had diabetes, 32% had high cholesterol, 60% had smoked, and 19% had hypertension. Diagnoses of dementia were determined by reviewing medical records from January 1994 to April 2003. According to the investigators, 721 participants (8.2%) had a diagnosis of dementia.

Hypertension, high cholesterol, diabetes, and smoking at midlife were each associated with an increased risk of dementia. Participants with hypertension were 24% more likely to have dementia; those with high cholesterol were 42% more likely to have dementia, those with diabetes were 46% more likely to have dementia, and those who reported ever having smoked were 26% more likely to have dementia.

Dr. Whitmer and her colleagues also found that compared with participants with no cardiovascular risk factors, those with one risk factor were 27% more likely to have dementia; those with two risk factors were 70% more likely to have dementia; and those with three or four risk factors were more than twice as likely to have dementia.

The researchers offered several possible explanations for their results. They noted that the association between diabetes and dementia “may be due to the cumulative effects of both microvascular and macrovascular changes in the brain.” They said that future studies should focus on determining whether improving glycemic control among patients with diabetes would lower the risk of dementia. The researchers also said that the association between high cholesterol and dementia “may be due to increased production of β-amyloid or presence of apolipoprotein E ε4 allele.” They pointed out that “a number of observational studies have shown that use of cholesterol lowering drugs … reduces risk of cognitive impairment and dementia.”

Dr. Whitmer’s research group concluded that earlier treatment of cardiovascular disease might lower the risk of dementia. “Future studies are needed to elucidate the mechanisms due to the implications for earlier prevention,” they said.

Whitmer RA, Sidney S, Selby J, et al. Midlife cardiovascular risk factors and risk of dementia in late life. Neurology. 2005;64:277-281.

NO BENEFIT OF EARLY SURGERY IN PATIENTS WITH INTRACEREBRAL HEMORRHAGE

Favorable outcomes in patients with spontaneous supratentorial intracerebral hemorrhage who are treated with early surgery do not seem to differ significantly from those in patients who receive initial conservative treatment, according to a study conducted by A. David Mendelow, PhD, and colleagues. Dr. Mendelow is Head of the Department of Neurosurgery at Newcastle General Hospital and Professor of Neurosurgery at the University of Newcastle upon Tyne, both in the United Kingdom.

According to the study, which was published in the January 29 Lancet, a total of 1,033 patients with spontaneous supratentorial intracerebral hemorrhage were randomly assigned to early surgery (n = 503) or initial conservative treatment (n = 530). Patients were between the ages of 19 and 93 and more than half were men. According to the researchers, “time from ictus to randomization varied from 2 to 72 hours, with half being randomized within 20 hours. A fifth of patients presented in coma (ie, Glasgow coma score ≤ 8), whereas two fifths had a score of 13 or above.” They also noted that “about two fifths of the hematomas were lobar and a similar number were located in the basal ganglia or thalamic regions, with the rest extending through both sites. Slightly more hematomas were located on the left side than the right.”

Complete follow-up data were available for 965 patients. Craniotomy was the most frequent surgical technique, used in 465 patients. Of patients assigned to initial conservative treatment, 140 underwent surgery, after an initial period of observation, due to rebleeding, neurologic deterioration, and raised intracranial pressure, as well as various other reasons. Results indicated that at six months, 26% of patients assigned to early surgery had a favorable outcome, compared with 24% of patients assigned to initial conservative treatment.

Little difference was found between the two treatments. However, “a favorable outcome from early surgery was more likely if the hematoma was 1 cm or less from the cortical surface…. A favorable outcome from early surgery was also more likely if the intended method of evacuation was craniotomy,” said the researchers. Also, poor outcome was seen in patients with coma, particularly in those who were assigned to early surgery.

The researchers concluded that “there is insufficient evidence to justify a general policy of early operative intervention in patients with spontaneous supratentorial intracerebral hemorrhage, compared with one of initial conservative treatment. Patients with superficial hematomas might benefit from surgery, especially by craniotomy, but this beneficial effect needs to be established.”

In an accompanying editorial, Takahiro Nakano, MD, PhD, and Hiroki Ohkuma, MD, said they do not believe that the study by Dr. Mendelow’s research team directly challenges the usefulness of surgery for spontaneous intracerebral hemorrhage because the surgery group was limited to patients who had early surgery. They noted that 26% of patients assigned to initial conservative treatment required surgery. “These crossovers should be regarded as candidates for surgery…. Surgery in the early stage might have prevented subsequent brain edema associated with neurological deterioration in these patients,” they said.

Drs. Nakano and Ohkuma also pointed out that in addition to appropriately identifying subgroups of patients who would benefit from surgery, “it is important to improve operative techniques to obtain good surgical results.”

Mendelow AD, Gregson BA, Fernandes HM, et al. Early surgery versus initial conservative treatment in patients with spontaneous supratentorial intracerebral haematomas in the International Surgical Trial in Intracerebral Haemorrhage (STICH): a randomised trial. Lancet. 2005;365:387-397.
Nakano T, Ohkuma H. Surgery versus conservative treatment for intracerebral haemorrhage—is there an end to the long controversy? Lancet. 2005;365:361-362.

REHAB SERVICES OFFER STROKE PATIENTS EARLY HOSPITAL DISCHARGE

Services that provide stroke patients with rehabilitation and support in a community setting seem to be effective in reducing long-term dependency and admission to institutional care, as well as shortening hospital stay, according to a study conducted by Peter Langhorne, PhD, and colleagues. Their meta-analysis of 11 trials was published in the February 5 Lancet.

The trials included 1,597 patients (mean or median age, 68 to 78) with a clinical diagnosis of stroke. Patients received either conventional care or an early supported discharge (ESD) service intervention. According to the investigators, the ESD service interventions usually consisted of a multidisciplinary team—comprising physiotherapy, occupational therapy, and speech and language therapy staff with medical, nursing, and social-work support—that provided in-hospital care, planned hospital discharge, and, in most cases, provided rehabilitation at home or through a community service.

The investigators found that “there was a reduced risk of death or dependency equivalent to six fewer adverse outcomes for every 100 patients receiving an ESD service.” Patients assigned to ESD had shorter hospital stays, by eight days, compared with those assigned to conventional care. Also, improvements were seen in extended activities of daily living scale scores, the odds of living at home, and reporting satisfaction with services. The greatest benefits were seen in stroke patients with mild to moderate disability, the authors noted.

Dr. Langhorne’s research group concluded that “appropriately resourced and coordinated ESD teams can offer a further effective service option for a selected group of stroke patients and should be considered, in addition to organized inpatient (stroke unit) care, as part of a comprehensive stroke service.”

In an accompanying commentary, Ronald Meijer, MD, and Jacques van Limbeek, MD, PhD, questioned the methods used in Dr. Langhorne’s study to identify eligible patients for ESD services and suggested that the eight-day reduction in the length of hospital stay could be due to different causes.

According to their interpretation of Dr. Langhorne’s study, “admission to ESD services will be the optimum choice for patients who: no longer need medical and nursing treatment that only a hospital can provide; have moderate stroke severity; can return home because they can care for themselves or they have the help of professional care, family care, or both; need rehabilitation that can be provided at home; do not need rehabilitation that cannot be provided at home; live at a considerable distance from the hospital or rehabilitation services and for whom the combination of traveling to an outdoor service with exercise could be too tiring; or who would benefit most from situational learning instead of trying to generalize learned skills.”

Langhorne P, Taylor G, Murray G, et al. Early supported discharge services for stroke patients: a meta-analysis of individual patients’ data. Lancet. 2005;365:501-506.
Meijer R, van Limbeek J. Early supported discharge: a valuable alternative for some stroke patients. Lancet. 2005;365:455-456.

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