A cohort study on the relationship between blood pressure levels and the mortality of cerebro-cardiovascular diseases in Guangzhou workers

Abstract

OBJECTIVE: To study the relative risk (RR) of mortalities of cerebro-cardiovascular diseases (CVD) in Guangzhou workers with hypertension. METHOD: Prospective cohort study was conducted in 78,379 workers, aged >or= 35, from 399 factories. Cox regression model were mainly used for data analysis. RESULTS: (1) There were 48,705 male and 29,674 female workers in the cohort. All workers were followed-up for 8 years. 363 CVD deaths (male 305, female 58) mainly died of stroke, coronary heart disease and hypertension. The crude mortalities were 78.58/100,000 person years in male and 24.55/100,000 person years in female. (2) Compared with the optimal or normal blood pressure (ONBP), the RR (95%) of CVD deaths with high blood pressure (HBP) were 6.19 (4.85 - 7.91) in male and 2.78 (1.59 - 4.85) in female. In male, compared with ONBP, the RR of CVD deaths without illness but with 1st-grade HBP at baseline, and of those suffered non-CVD but with 1st-grade HBP at baseline, and of those suffered CVD with 2nd-grade HBP at baseline were 3.98, 3.25 and 3.15 respectively (P < 0.01). (3) After stratifying of age, smoking, drinking, educational levels and occupational exposure, the RR of CVD deaths was higher in those who were younger, or ever-smoking, non-drinking, higher educational level, exposed to occupational hazards and with hypertension. CONCLUSION: There is relationship between BP levels and CVD mortality. High BP may affect CVD deaths at younger age. Comprehensive measures should be used to reduce the risk of CVD deaths.

目的 分析工人高血壓與心腦血管疾病 (CVD)死亡的相對危險度 (RR) ,探討減少工人CVD死亡危險性的預防辦法。方法 由廣州 399家工廠年齡 35歲或以上的 78379名工人組成隊列 ,進行前瞻性研究。資料處理采用分層和多因素調整統計分析方法 (Cox模型 )。結果 (1)隊列中男4870 5名、女 2 96 74名 ,追蹤 8.0年 ,CVD死亡 36 3人 ,男 30 5人、女 5 8人 ,粗死亡率分別為 78.5 8/ 10萬人年和 2 4.5 5 / 10萬人年 ,主要死于腦卒中、冠心病和高血壓。 (2 )與理想或正常血壓比 ,高血壓CVD死亡的RR(95 % )分別為男 6 .19(4.85～ 7.91)、女 2 .78(1.5 9～ 4.85 ) ;男性工人基線無患病者和非CVD患者Ⅰ級高血壓CVD死亡的RR和CVD患者Ⅱ級高血壓CVD死亡的RR明顯增加 ,分別為 3.98、3 .2 5和 3 .15 ,理想或正常血壓與Ⅰ級高血壓和Ⅱ級高血壓CVD死亡的RR增加趨勢差異有顯著性 (P<0 .0 1)。(3)按年齡、吸煙、飲酒、文化程度和職業接觸有害因素分層后 ,年輕、吸煙、不飲酒、文化程度較高者以及職業接觸有害因素者的高血壓患者CVD死亡RR較高。結論 血壓水平與心腦血管疾病死亡率呈連續性相關 ,高血壓對CVD死亡的影響在較年輕時已經出現 ;應采用綜合預防辦法減少CVD死亡危險性。