Atorvastatin increases HDL cholesterol in hypercholesterolemic patients. Evidence of a relationship with baseline HDL cholesterol.
OBJECTIVE
It has been reported that atorvastatin increases high-density lipoprotein cholesterol (HDL-C) more in patients with low than in those with high baseline HDL-C levels. This may have a biological explanation, but also suggests a statistical artifact known as the regression to the mean.


RESULTS
Atorvastatin 10 mg/day led to a 4% increase in HDL-C after two months in 67/121 patients with hypercholesterolemia (55%), who had lower baseline HDL-C levels than the patients in whom HDL-C did not increase. In the patients with baseline HDL-C below the median, HDL-C significantly increased whereas no change was observed in patients with baseline HDL-C above the median. The correlation coefficient between pre- and post-treatment HDL-C was 0.84, thus suggesting a regression to the mean. However, the regression artifact did not entirely explain the increase in HDL-C in patients with low baseline HDL-C or the lack of an increase in those with high baseline HDL-C. The adjusted mean increase was 5.4% in patients with low pretreatment HDL-C, and 2.4% in the patients with high pretreatment HDL-C. Multiple regression analysis with the changes in HDL-C as the dependent variable showed that baseline HDL-C and the changes in serum triglycerides independently contributed to the change in HDL-C levels.


CONCLUSIONS
Atorvastatin 10 mg/day increases HDL-C more in patients with low pretreatment HDL-C levels, an effect that seems to be related to the hypotriglyceridemic activity of the drug.
Department of Internal Medicine, University of Milan, Maggiore Hospital IRCCS, Milan, Italy. adriana.branchi@unimi.it
A
A
Branchi
A M
AM
Fiorenza
A
A
Torri
F
F
Muzio
C
C
Berra
E
E
Colombo
E
E
Dalla Valle
A
A
Rovellini
D
D
Sommariva
D000328:Adult; D000368:Aged; D000924:Anticholesteremic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D000069059:Atorvastatin; D008076:Cholesterol, HDL / Q000097:blood / Q000187:drug effects*; D003327:Coronary Disease / Q000097:blood / Q000188:drug therapy; D005260:Female; D006538:Heptanoic Acids / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011758:Pyrroles / Q000494:pharmacology / Q000627:therapeutic use*; D012044:Regression Analysis; D014280:Triglycerides / Q000097:blood
D000924:Anticholesteremic Agents; D008076:Cholesterol, HDL; D006538:Heptanoic Acids; D011758:Pyrroles; D014280:Triglycerides; D000069059:Atorvastatin