Background and Purpose:We sought to determine the type-specific prevalence of dementia and its risk factors in elderly persons from the Japanese community of Hisayama.Methods: We studied the prevalence of dementia in 887 Hisayama residents (353 men and 534 women) aged 65 years or older (screening rate, 94.6%) using various items of clinical information, neurological examination, and dementia scales. We also studied brain morphology in 50 of 59 determined to have dementia by computed tomography or autopsy during the subsequent 54 -month period. Factors relevant to dementia were compared between 27 patients with vascular dementia and 789 control subjects without dementia in a retrospective fashion.Results: The prevalence rate of dementia among Hisayama residents aged 65 or older was estimated at 6.7%, with a females to males ratio of 1:2. Among 50 cases of dementia in which brain morphology was examined, the frequency of vascular dementia was 56%; this rate was 2.2 times higher than that for senile dementia of the Alzheimer type. Aging, hypertension, electrocardiographic abnormalities, and high hematocrit were significantly (p<0.05) and independently associated with the occurrence of vascular dementia.Conclusions: Prevalence of dementia among the Hisayama residents was relatively identical to that previously reported, but vascular dementia was more predominant Risk factors for vascular dementia were similar to those for lacunar infarcts. Control of hypertension may be a key to reducing dementia among the Japanese population. (Stroke 1992;23:798-803) KEY WORDS • dementia • epidemiology • Japan • risk factors

Inflammatory responses contribute to host defense against harmful organisms and allergens, whereas a failure of immune tolerance can cause chronic inflammation including asthma. The lung has several innate myeloid cell subsets. Among these subsets, there are two types of macrophages: alveolar macrophages (AMs) and interstitial macrophages (IMs). However, compared with AMs, the role of IMs in lung homeostasis remains poorly understood. In this study, we characterized AMs and IMs in healthy and inflammatory conditions. Pulmonary IMs constitutively produce the anti-inflammatory cytokine IL-10 through activation of the TLR4/MyD88 pathway in a microbiota-independent manner. In addition to IMs, Foxp3 T cells show persistent IL-10 expression in the lung, with IL-10-producing IMs more prevalent than Foxp3 T cells. IMs, but not Foxp3 T cells, increased IL-10 production in house dust mite (HDM)-challenged mice, a model of human asthma. HDM-challenged Il10 mice exhibited severe lung pathology characterized by neutrophilia compared with that of wild-type mice. In addition, transplantation of wild-type IMs reduced neutrophilic inflammation, goblet cell mucus production and decreased expression of lung IL-13 and T17-related neutrophil-activating cytokines such as IL-17, GM-CSF, and TNF-α. Together these results demonstrate that IL-10-producing IMs negatively regulate T2- and T17-mediated inflammatory responses, helping prevent neutrophilic asthma.

The incidence of intracerebral hemorrhage over 13 years is compared between two Hisayama cohorts. Among men aged 40 years or older, the annual incidence declined significantly from 3.1/1,000 in the early cohort (1961-1970) to 1.2/1,000 in the recent cohort (1974-1983). Massive ganglionic hemorrhage decreased, while small or medium-sized intracerebral hemorrhage increased in the recent cohort on pathologic or computed tomographic examination. These trends could be due to the reduced prevalence of hypertension in the Hisayama population. The association of serum total cholesterol with intracerebral hemorrhage is discussed based on the results during a 22-year follow-up period.

We compared type-specific prevalences of dementia between two surveys of Hisayama residents ≥ 65 years old conducted in 1985 and 1992. The overall age-adjusted prevalence was greatly decreased from 5.4% in 1985 to 3.3% in 1992 for men, while it was changed little from 7.5 to 6.3% for women. The prevalence of vascular dementia (VD) decreased during the intervening 7 years in men but not in women. The prevalence of Alzheimer’s type (SDAT) was the same in either sex. The ratio of VD to SDAT prevalence was 1.8 in 1985 but fell to 1.1 in 1992. The background factors responsible for this change are discussed.

No abstract