Cigarette Smoking as a Risk Factor for Stroke Death in Japan

Abstract

Background and Purpose-Some previous Japanese cohort studies failed to show an association between smoking and stroke risk. Because such an association has been noted in other populations, this issue should be re-examined in a recent representative Japanese cohort with a higher total cholesterol level. Methods-A total of 9638 men and women aged 30 years and older without a history of cardiovascular disease (CVD) at baseline in 1980 were followed-up for 14 years. Results-We observed 203 stroke deaths (107 cerebral infarctions, 45 cerebral hemorrhages, and 51 others), 191 heart disease deaths, and 413 CVD deaths. The average serum total cholesterol level was Ϸ4.91 mmol/L. Cox proportional hazard ratios were calculated adjusting for age, systolic blood pressure, and other conventional risk factors. The hazard ratios for men who smoked 1 to 20 cigarettes/day for all strokes, cerebral infarction, and cerebral hemorrhage were 1.60 (95% CI, 0.91 to 2.79), 2.97 (CI, 1.27 to 6.98), and 0.42 (CI, 0.16 to 1.09), respectively, and for those who smoked Ն21 cigarettes/day, they were 2.17 (CI, 1.09 to 4.30), 3.26 (CI, 1.11 to 9.56), and 0.68 (CI, 0.20 to 2.33), respectively. For women who smoked Ն21 cigarettes/day, the hazard ratio for all strokes was 3.91 (CI, 1.18 to 12.90). For CVD, all heart disease, and ischemic heart disease, the hazard risks of smoking were significant (1.49 to 4.25) for men but not significant for women. Conclusions-Smoking in a cohort with moderate serum total cholesterol level was a potent risk factor for stroke, especially cerebral infarction, for both men and women, and for CVD and ischemic heart disease for men.

Relationship of elevated casual blood glucose level with coronary heart disease, cardiovascular disease and all-cause mortality in a representative sample of the Japanese population. NIPPON DATA80

“…Details of these cohorts have been previously reported [10][11][12][13][14]. Briefly, 13,771 participants were randomly selected in 300 districts from the overall population aged 30 years or older in Japan by the Japanese Ministry of Health and Welfare.…”

“…Permission to use National Vital Statistics was obtained from the Management and Coordination Agency, Government of Japan. Approval for this study was obtained from the Institutional Review Board of Shiga University of Medical Science (number [12][13][14][15][16][17][18]2000).…”

Medical expenditures of men with hypertension and/or a smoking habit: a 10-year follow-up study of National Health Insurance in Shiga, Japan

“…The mean level of blood pressure is higher in Japan than in Western countries, 17,35,[37][38][39][40][41] despite a substantial decline in blood pressure during the past four decades. 42 In addition, the prevalence of smoking among Japanese men remains much higher compared with men in the West, [8][9][10]17,35,37,41,43 although there has been a trend for a decline in smoking. 42 As a result, approximately 70-80% of Japanese men have hypertension and/or a smoking habit, 16,23 which would directly contribute to as much as 20% of the entire medical expenditures in this population.…”

“…34 Therefore, the participants in this study represented approximately 38% of all NHI beneficiaries aged 40-69 years living in this area. The analysis was conducted only for men, because the prevalence of smokers is quite low among Japanese women; [8][9][10]16,23,35 our data showed that current smokers and former smokers accounted for 3.4% (n¼87) and 0.5% (n¼14), respectively, of 2596 female participants. Of the 1939 male participants, 231 were excluded because they were former smokers (n¼229) or there was no information on smoking habit at the baseline survey (n¼2).…”

“…[4][5][6][7] Hypertension is a major contributor to cardiovascular diseases in the Asia-Pacific region. 3 Furthermore, cigarette smoking, which leads to cardiovascular disease as well as cancer and respiratory disease, [7][8][9][10][11][12] is also a major health burden in the Asia-Pacific region because of its popularity among men; 13 nearly two-thirds of the world's smokers live in 10 countries, and most of them are in that region. 14 Thus, both hypertension and a smoking habit might be more important determinants of human health than other risk factors in the Asia-Pacific region.…”