Hormone therapy continues to be a favourable option in the management of menopausal symptomatology, but the associated risk-benefit ratios with respect to neurodegenerative diseases remain controversial. The study aim was to determine the relation between menopausal hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in human subjects. A literature search was performed in PubMed/Medline, Cochrane collaboration, and Scopus databases from onset of the database to September 2019. Random-effects model was used to estimate pooled odd ratio (OR) and 95 % confidence intervals (CI). Subgroup analysis was performed based on the type and formulation of hormone. In addition, the time-response effect of this relationship was also assessed based on duration of hormone therapy. Associations between hormone therapy and Alzheimer's disease, dementia, and Parkinson's disease in menopausal women were reported in 28 studies. Pooled results with random effect model showed a significant association between hormone therapy and Alzheimer's disease (OR 1.08, 95 % CI 1.03-1.14, I2: 69 %). This relationship was more pronounced in patients receiving the combined estrogen-progestogen formulation. Moreover, a significant non-linear time-response association between hormone therapy and Alzheimer's disease was also identified (Coef1 = 0.0477, p1<0.001; Coef2 = -0.0932, p2<0.001). Similarly, pooled analysis revealed a significant association between hormone therapy and all-cause dementia (OR 1.16, 95 % CI 1.02-1.31, I2: 19 %). Interestingly, no comparable relationship was uncovered between hormone therapy as a whole and Parkinson's disease (OR 1.14, 95 % CI 0.95-1.38, I2: 65 %); however, sub-group analysis revealed a significant relationship between the disease and progestogen (OR 3.41, 95 % CI 1.23-9.46) or combined estrogen-progestogen formulation use (OR 1.49, 95 % CI 1.34-1.65). Indeed, this association was also found to be driven by duration of exposure (Coef1 = 0.0626, p1 = 0.04). This study reveals a significant direct relationship between the use of certain hormonal therapies and Alzheimer's disease, all-cause dementia, and Parkinson's disease in menopausal women. However, the association appears to shift in direct after five years in the context of Alzheimer's disease, adding further weight to the critical window or timing hypothesis of neurodegeneration and neuroprotection.
Patients with major presentations of alopecia experience physically harmful effects and psychological comorbidities, such as depression and anxiety. Oral minoxidil (OM) has been suggested by dermatologists as a potential remedy; however, its effectiveness remains unclear. This systematic review aims to collate published studies and to analyze the effect of OM among patients diagnosed with any type of alopecia. For this systematic review, Medline/PubMed, Cochrane Central, EMBASE, Web of Sciences, and Latin American and Caribbean Health Sciences Information System were searched for relevant studies from inception to September 21, 2019. Of 1960 studies retrieved in several electronic databases and three additional records identified though reference list from potentially eligible studies, nine studies (one randomized controlled trial and eight nonrandomized controlled trials) met the requirements and were used in our analysis. Although we found positive effects in favor of OM, this should be interpreted cautiously due to very low quality of the evidence of outcomes in the selected studies. Definitive conclusions are not possible without high-quality trials. This review has highlighted the absence of high-quality randomized controlled trials evaluating OM in the treatment of various types of alopecia. Given the mild adverse events of OM, future studies should also analyze doses and duration to maximize efficacy and decrease side effects.