The ageing of the global population is the most important medical and social demographic problem worldwide. The World Health Organization (WHO) has defined healthy ageing as a process of maintaining functional ability to enable wellbeing in older age. The WHO, Member States and Partners for Sustainable Development Goals have created a Global Strategy and Action Plan for Ageing and Health for 2016-2020 and its continuation with the WHO programme The Decade of Healthy Ageing 2020-2030. The WHO has established main priorities such as supporting country planning and action, collecting better global data and promoting research on healthy ageing, aligning health systems to the needs of older people, laying the foundations and ensuring the human resources necessary for long-term integrated care, undertaking a global campaign to combat ageism, and enhancing the global network for age-friendly cities and communities. There are several reports of coordinated preventive health and social health initiatives in well developed countries. However, there is little evidence on the application of the active ageing frameworks in developing countries. Greater national capacities and closer monitoring of the progress through age-disaggregated data is needed to effectively implement the intended programmes on healthy ageing.

The hair cycle and hair follicle structure are highly affected by various hormones. Androgens—such as testosterone (T); dihydrotestosterone (DHT); and their prohormones, dehydroepiandrosterone sulfate (DHEAS) and androstendione (A)—are the key factors in terminal hair growth. They act on sex-specific areas of the body, converting small, straight, fair vellus hairs into larger darker terminal hairs. They bind to intracellular androgen receptors in the dermal papilla cells of the hair follicle. The majority of hair follicles also require the intracellular enzyme 5-alpha reductase to convert testosterone into DHT. Apart from androgens, the role of other hormones is also currently being researched—e.g., estradiol can significantly alter the hair follicle growth and cycle by binding to estrogen receptors and influencing aromatase activity, which is responsible for converting androgen into estrogen (E2). Progesterone, at the level of the hair follicle, decreases the conversion of testosterone into DHT. The influence of prolactin (PRL) on hair growth has also been intensively investigated, and PRL and PRL receptors were detected in human scalp skin. Our review includes results from many analyses and provides a comprehensive up-to-date understanding of the subject of the effects of hormonal changes on the hair follicle.

Premature ovarian insufficiency (POI) is a type of hypergonadotropic hypogonadism caused by impaired ovarian function before the age of 40. Due to the hypoestrogenism, women with POI experience a variety of health complications, including an increased risk of bone mineral density loss and developing osteopenia and osteoporosis, which poses an important problem for public health. Purpose: The aim of this study was to evaluate and compare the values of bone mineral density (BMD), T-score and Z-score within the lumbar spine (L1-L4) using the dual energy X-ray absorptiometry method. The dual-energy X-ray absorptiometry (DXA) scans described in this original prospective article were performed at the time of POI diagnosis and after treatment with sequential hormone replacement therapy (HRT). Materials and methods: This study included 132 patients with a mean age of 31.86 ± 7.75 years who had been diagnosed with idiopathic POI. The control group consisted of 17 healthy women with regular menstrual cycles, with a mean age of 23.21 ± 5.86 years. Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17-estradiol (E2), prolactin (PRL), testosterone (T), dehydroepiandrosterone sulfate (DHEA-S), thyroid-stimulating hormone (TSH), free thyroxine (fT4), insulin, and fasting serum glucose were measured. Lumbar spine (L1-L4) BMD was assessed by means of dual-energy X-ray absorptiometry. DXA scans were performed at the time of diagnosis and following treatment with sequential hormone replacement therapy (HRT) comprised of daily oral 2 mg 17-β-estradiol and 10 mg dydrogesterone. The mean time of observation was 3 ± 2 years. Results: Patients in the POI group presented with characteristic hypergonadotropic hypogonadism. They had a significantly decreased mean lumbar spine BMD when compared to healthy controls (1.088 ± 0.14 g/cm2) vs. 1.150 ± 0.30 g/cm2) (p = 0.04) as well as a decreased T-score (0.75 ± 1.167 vs. −0.144 ± 0.82) (p = 003). There was a significant increase in BMD (1.088 ± 0.14 vs. 1.109 ± 0.14; p < 0.001), T-score (−0.75 ± 1.17 vs. −0.59 ± 1.22; p < 0.001), and Z-score (−0.75 ± 1.12 vs. −0.49 ± 1.11; p < 0.001) after the implementation of HRT when compared to pre-treatment results. Conclusions: In conclusion, this study has demonstrated that patients with POI often have decreased bone mineral density and that the implementation of HRT has a significant and positive influence on bone mass. The implementation of full-dose HRT and monitoring of bone status is particularly important in these patients.