The Association Between Estrogen And Parkinson Disease

[Objective] The objective is to discuss the sex difference of Parkinson disease (PD) and its probable causes.[Methods] The clinical data of 1196 PD cases ,who were diagnosed at the Extrapyramidal Disease Center in TianJin General Hospital, were analyzed retrospectively. All the PD patients were stratified according to sex and age at onset. Firstly, the men/women relative ratio at different onset-age stage was calculated. Secondly, the constituent ratio (CR) at different onset-age stage was compared between male and female PD patients. Thirdly, the effects of heredity, environmental toxin exposure or head trauma were involved in the analysis between male and female PD cases.[Results] Sex difference did exist in PD patients. The percentage of male PD was higher than that of female PD at different onset-age stage. The average men/women relative ratio was 1.53. The constituent ratio at different stage in female patients was not the same as that in male ones. Before 40 years old, the CR in men was higher than that in women. At the 40 to 59 years old stage, female patients increased abruptly, from 2.96% before 40 years old to 42.92%. While in male patients, it was just from 7.47% to 38.73%. As to the effects of heredity and head trauma, there was no significant difference between men and women (P>0.9). Male patients had more chance to expose to such toxin as heavy metals, farming poison and etc (P<0.05). [Conclusion] Men are prone to suffer from PD comparing with women. For women, the 40 to 59 years old stage means perimenopause and menopause, the level of estrogen decreased sharply, during this period, the number of female PD patientsrose remarkably. This indicated that reduced estrogen level is a risk factor of PD. More exposure to toxin for men may also contribute to a greater risk of PD in men. In brief, the lower risk of PD in women is probably owing to the neuro-protection by estrogen and less toxicant exposure.[Objective] We studied the association between Parkinson disease and such factors reflecting endogenous estrogen level as reproductive characteristics, mastadenoma or breast cancer, uterine leiomyomas and obesity in women.[Methods] A case-control study was performed among 119 women cases with idiopathic PD and 144 sex and age-matched control subjects from the same residential area. Each case and control was interviewed face to face. A structured questionnaire included reproductive characteristics such as age at menarche> age and type of menopause n parity > gender of children miscarriage and abortion n progesterone and oral contraceptive use, as well as past histories(mastadenoma or breast cancer> uterine leiomyomas). Height and weight were measured when they were interviewed. Statistical analyses were carried out using unconditional logistic regression.[Results] PD cases have experienced later menarche (OR=1.305, 95% CI: 1.134-1.503) > shorter fertile life duration (OR=0.900, 95% CI:0.840~0.964), more parity (OR=1.923, 95%CI: 1.518-2.437) and longer cumulative span of pregnancy (OR=1.064, 95% CI: 1.040-1.089) significantly than control subjects. In addition, PD cases were associated with an early menopause than control subjects, though it was not statistically significant. An inverse association between PD and BMI>24 kg/m2 (OR=0.022, 95% CI: 0.005-0.094) was found. And there was also an inverse relation between PD and mastadenoma or breast cancer (OR=0.140, 95% CI: 0.072-0.271). [Conclusion] Endogenous estrogen plays an important role in the development ofPD. There is an increased risk of PD in reduced estrogen level conditions, while high endogenous estrogen is protective against PD.[Objective] To explore the relationship between postmenopausal estradiol level andPD rislu severity and progression degree.[Methods] The serum estradiol level was measured in 56 postmenopausal PDpatients and 25 controls through chemiluminescence immunoassay. Case-controlstudy was used to investigate the difference of estradiol between two groups. AmongPD cases, the effects of estradiol on PD UPDRS score > severity and progressiondegree of PD were analyzed using Spearman rank corelation test.[Results] Both groups were similar in age and duration after menopause. Theestradiol level in 30 cases and 20 controls was less than lOpg/ml, and the mean value(x±SD) were 26.98±13.77pg/ml and 24.28±20.76pg/ml in PD and control group(P>0.5) respectively. No association was found between estradiol level and severity or progression of PD (P>0.05).[Conclusion] There was no significant correlation between endogenous postmenopausal estradiol level and PD. Maybe the low estrogen level at postmenopause stage did not exert strong effect on PD as high estrogen level did during the normal menstrual period. The next step of our research is to investigate the association between estrogen and PD in premenopausal PD women by enlarging sample size, or to perform a prospective study about the effect of estrogen level on PD risk or to study the effect of ERT on Parkinson disease.[Objective] The purpose of this study was to investigate the association betweenfour estrogen receptor(ER) gene polymorphisms and Parkinson disease.[Methods] One hundred and fifteen PD cases and 116 controls were genotyped forPvuIL Xbal polymorphisms of ERct gene and Alul -. Rsal polymorphisms of ER.0gene through polymerase chain reaction- restriction fragment length polymorphism(PCR-RFLP) method. The relationship between each genotype or allele frequenciesand PD was analyzed using chi-square test.[Results] No association was observed between an increased risk of PD and theestrogen receptor genotypes or allele frequencies derived from PvuIK XbaK Alul ^Rsal digestion. Analysis restricted to PD with dementia and controls yielded similarfindings. While stratifying PD patients by age at onset, we found the C allele ofPvuII digestion in ERa gene was more frequent in patients with a late age at onset(PO.01).[Conclusion] Genetic variation in estrogen receptor a gene may influence the age atonset of Parkinson disease.