[Environmental factors possibly associated with onset of senile dementia]

Factors associated with senile dementia have not been clarified, and factors, especially those in the living environment which seem to have a close link to the dementia need to be analysed. We conducted a case-control study targeting patients within the jurisdiction of Nagahama Public Health Center in Shiga and Hikone city, who are diagnosed to have senile dementia of the Vascular type, senile dementia of the Alzheimer type, and senile dementia of the Mixed type, and compared them to age matched controls. The outcome of the study by Matched pair analysis (McNemar's test) before the onset of the senile dementia were as follows. 1 The factors related to senile dementia of the vascular type were: Previous histories (Matched Odds Ratio (MOR): 8.0 p < 0.05), disturbance of the lower limbs (MOR = 8.0 p < 0.05). Environmental factors were: strong preference for sweets (MOR = 8.0 p < 0.05 female), smoking (MOR = 3.7 p < 0.10), lower utilization of health care (MOR = 3.3 p < 0.10), such as periodic medical check (MOR = 0/6 p < 0.10), sleep (MOR = 0/5 p < 0.10), less commitment to hobbies (MOR = 2.6 p < 0.10), such as handicrafts (MOR = 0/5 p < 0.10) etc, less intercourse with relatives (MOR = 0/9 p < 0.01), not living together with children's family (MOR = 0.20 p < 0.05 female), and death (MOR = 8/0 p < 0.05) or hospitalization (MOR = 9.0 p < 0.05) of a family member. 2 The factors related to senile dementia of the Alzheimer type and the Mixed type were: some previous histories (MOR = 8.0 p < 0.05), less disturbance of gait (MOR = 0/5 p < 0.10). Environmental factors were: lower utilization of health care, such as periodic medical check (MOR = 0.18 p < 0.05), and lower participation in exercise (MOR = 0/5 p < 0.10) etc, less association with neighbors (MOR = 0.11 p < 0.05), less participation in community activities (MOR = 0.11 p < 0.05), not living together with children's family (MOR = 0/8 p < 0.05), relocation (MOR = 5/0 p < 0.10) and retirement (MOR = 5/0 p < 0.10).