PROGNOSTIC VALUE OF SERUM LIPOPROTEIN(A) LEVELS ON LONG-TERM MORTALITY IN A LARGE SAMPLE OF SUBJECTS IN PRIMARY CARDIOVASCULAR PREVENTION: DATA FROM THE BRISIGHELLA HEART STUDY

Objectives: To assess whether serum Lp(a) levels can significantly influence long-term survival in subjects with an equal general cardiovascular-risk-profile. Methods: This study involved a Brisighella Heart Study cohort sample of 1172 adult subjects (M:573;F:599; aged 40-69) with no cardiovascular-diseases at enrollment. According to the CUORE project risk-charts (Italian-specific risk-charts), individuals were stratified into low-(n=865), intermediate-(n=232) and high-(n=75) cardiovascular-risk-groups. Kaplan-Meier 25-year survival analysis was carried out examining each risk class. The log-rank statistic was used to estimate the survival of subjects with/without elevated serum Lp(a) levels compared to the population’s median (18 mg/dl). Survival functions were age-adjusted considering the subjects’ starting age (if higher/lower than the study-population's mean, which was 56). Finally, we constructed a ROC curve in order to evaluate whether serum Lp(a) concentration was an independent long-term mortality prognosticator. Results: In the low-cardiovascular-risk-group, no differences were observed in the 25-year survival regarding increased Lp(a) levels. According to the Mantel-Cox test, subjects at intermediate-cardiovascular-risk, aged 56-69 and with elevated Lp(a) levels, showed a significantly higher survival-time-estimate rather than subjects with the same age but lower Lp(a) levels (15,1±0,8vs12,8±1 years, P=0,01). However, first group’s mortality-rate (60,2%) was higher compared to the second one (39,8%). In the high-cardiovascular-risk-group, having only older subjects than the population's mean prevented us from any statement. Furthermore, in this group, dosing serum Lp(a) appeared a mildly accurate, though predictive, test of long-term mortality (AUC=0,63,CI[0,50-0,76],P=0,05, with 17,5mg/dl best cut-off-value), losing any predictive power in subjects at low-/intermediate-cardiovascular-risk. Conclusions: Tightly controlling modifiable cardiovascular-risk factors is advisable in subjects with high serum Lp(a) levels.