OBJECTIVETo analyze the distribution of matrix metalloproteinase-3 (MMP-3) genotype and its association with the blood pressure profiles in Guangzhou rural population.

METHODSThis study was conducted among 680 rural residents aged 40-70 years (including 314 men and 366 women) from 3 villages in an rural area of Guangzhou. The blood pressures of the subjects were measured and blood samples were collected for genotype analysis using polymerase chain reaction and direct sequencing of the MMP-3 gene promoter region to detect the 5 adenines (5A)/6 adenines (6A) polymorphisms.

RESULTSThe frequencies of MMP-3 genotypes 6A/6A, 5A/5A, and 5A/6A were 82.6%, 1.8% and 15.6% among these residents, respectively. The distribution of MMP-3 genotypes and allele frequencies showed no significant gender- or age-related variations. The men with different genotypes (6A/6A vs 5A/6A+5A/5A) did not show significant differences in blood pressure levels, whereas the women with 5A/6A+5A/5A genotypes had higher systolic and diastolic blood pressures than those with a 6A/6A genotype. The allele 5A was highly frequent in the hypertensive residents as compared with the normotensive residents.

CONCLUSIONSThe 6A homozygote is the predominant genotype of MMP-3 in Guangzhou rural population, which has a significantly lower proportion of 5A homozygote than the Western populations. The 5A allele is associated with a high risk of hypertension especially in women and may affect both systolic and diastolic blood pressures.

Adult ; Age Distribution ; Aged ; Alleles ; Blood Pressure ; China ; epidemiology ; Female ; Gene Frequency ; Genotype ; Humans ; Hypertension ; epidemiology ; genetics ; Male ; Matrix Metalloproteinase 3 ; genetics ; Middle Aged ; Risk Factors ; Rural Population ; Sex Distribution

Objective To evaluate the efficacy,bleeding profile and safety of low-dose levonorgestrel-releasing intrauterine system (LNG-IUS 8) in Chinese healthy women of childbearing age.Methods A multi-center,open-label,single-arm clinical trial conducted at 16 centres in China enrolled 773 healthy women of childbearing age (mean age 31.6 years old,range 18 to 40 years old),who demanded contraception,from April 2006 to June 2013.All women placed LNG-IUS 8 for 3 years and then been followed up at 3,6,9,12,18,24,30,36 months.The efficacy variables including pregnancy rate and expulsion rate were analyzed using life table,while observing adverse events (AE) to evaluate the safety.The bleeding profile happened during the study was assessed using 90-day reference intervals (World Health Organization criteria).Results Eight pregnancies occurred among 773 women,resulting in a overall Pearl index of 0.42 per 100 women years.The 3-year cumulative pregnancy rate was 0.37 per 100 women years and the 3-year cumulative expulsion rate was 1.99 per 100 women years.The number of women with bleeding/spotting reduced and the bleeding/spotting days declined over time.Totally 219 AE were reported related to LNG-IUS 8 placements.The most common AE were vaginal bleeding (8.2％,63/773)and the ovarian cyst (6.2％,52/773).LNG-IUS 8 had an improving effect on dysmenorrhea that the percentage of women with dysmenorrhea as well as the days of dysmenorrhea decreased over time.The percentage of women satisfied or very satisfied with LNG-IUS 8 was 87.2％ (622/713).Conclusion LNG-IUS 8 is highly effective and safe for Chinese healthy women of childbearing age.