A recent study has revealed that men, 45 years and above, do not benefit when it comes to reducing their risk of heart attack or stroke after a jab of the pneumococcal vaccine. Their risk remains the same as those not vaccinated.
Dr. Hung Fu Tseng, of Kaiser Permanente Southern California, Pasadena, and colleagues conducted a study to examine the association between vaccination with pneumococcal vaccine and the risk of developing acute heart attack and stroke in men.
They took into account known and potentially important confounders (factors that can influence a study, leading to unexpected outcomes that improperly skew the results).
The study included Kaiser Permanente Northern and Southern California health plans, with 84,170 participants ages 45 to 69 years from the California Men's Health Study, who were recruited between January 2002 and December 2003, and followed up until December 31, 2007.
The cohort was similar to the population of health plan members and men who responded to a general health survey in California on important demographic and clinical characteristics.
Demographic and detailed lifestyle characteristics were collected from surveys. Vaccination records were obtained from the Kaiser Immunization Tracking System.
During follow-up, there were 1,211 first myocardial infarctions (MIs; heart attack) in vaccinated persons (rate of 10.7 per 1000 person-years) compared with 1,494 first MI events in unvaccinated individuals (6.07 per 1000 person-years).
For stroke, there were 651 events in vaccinated persons (5.3 per 1000 person-years) compared with 483 events in unvaccinated persons (1.9 per 1000 person-years).
After analysis of the data, the researchers found no evidence for an association between pneumococcal vaccination and reduced risk of acute MI or stroke.
"In addition, association was not observed either in the current smokers, men with history of diabetes, men with history of hypertension, or men of the low-risk group," said Tseng.
The study has been published in the latest issue of JAMA.