Bone mineral density in midlife long-term users of hormonal contraception in South Africa: relationship with obesity and menopausal status

Bone health and hormonal contraception

INTRODUCTION

Short-term and long-term steroid contraceptive systems are widely employed in adolescents and premenopausal women; they could induce variation in bone metabolism, but whether these changes increase the overall fracture risk is not yet clear.

EVIDENCE ACQUISITION

A systematic search of scientific publications about "hormonal contraceptives" and "bone metabolism" in reproductive age women was conducted.

EVIDENCE SYNTHESIS

In adolescent girl, combined oral contraceptives could have a deleterious effect on bone health when their onset is within three years after menarche and when they contain ethinyl estradiol at the dose of 20 mcg. In perimenopausal women, steroid contraceptives seem not influence bone health nor increase osteoporotic fractures risk in menopause. The oral progestogens intake is not related to negative effects on skeletal health. Depot medroxyprogesterone acetate (DMPA) induce a prolonged hypoestrogenism with secondary detrimental effect on healthy bone; the higher bone loss was observed at the DMPA dose of 150 mg intramuscular such as after long-term DMPA-users. Progestin-based implants and intrauterine devices have not negative effect on bone health.

CONCLUSIONS

Since sex-steroid drugs induce variations in hormonal circulating concentrations, they may negatively affect bone metabolism. Contraceptive choice should be tailored evaluating any possible effect on bone health. Clinicians should always perform a precontraceptive counselling to identify any coexisting condition that may affect bone health. Further randomized studies are needed to confirm these results.

Hormonal Contraception: Systemic Estrogen and Progestin Preparations

Combined hormonal contraception (CHC) are short-acting, reversible methods containing both estrogen and progestin. Available CHC methods include combined oral contraceptives, transdermal patches, and vaginal rings. The combined oral contraceptive remains the most commonly used contraceptive method in the United States. The general principles of CHC will be reviewed, including mechanism of action and effectiveness. Unless otherwise stated, these principles apply to all CHCs. When discussing clinical studies and specific considerations related only to pills, patches, or rings, the method(s) will be specified. Words that specify sex are used when discussing studies in which sex was specified.

Bone Mineral Density in Antiretroviral Therapy-Naïve HIV-1-Infected Young Adult -Women Using Depot Medroxyprogesterone Acetate or Nonhormonal Contraceptives in Uganda

Most studies evaluating BMD in human immunodeficiency virus (HIV)‐infected populations have focused on antiretroviral therapy (ART)‐experienced patients. In this study, the association between HIV‐1 and/or depot medroxyprogesterone acetate (DMPA) and BMD among untreated HIV‐1–infected women in a resource‐limited setting was assessed before long‐term exposure to ART. The data were then compared with that of the 2005–2008 United States National Health and Nutrition Examination Survey data for non‐Hispanic White and Black women. Women aged 18–35 years, recruited from health facilities in Kampala, Uganda, were classified based on their combination of HIV‐1 status and DMPA use: (i) HIV‐1–infected current DMPA users, (ii) HIV‐1–infected previous DMPA users, (iii) HIV‐1–infected nonhormonal‐contraceptive users, and (iv) HIV‐uninfected nonhormonal‐contraceptive users. All HIV‐1–infected women reported being ART‐naïve at baseline. BMD was measured at the lumbar spine, total hip, and femoral neck using DXA. Multivariate linear regression was used to assess the association between HIV‐1 and/or DMPA and BMD Z‐scores. Baseline data were analyzed for 452 HIV‐1–infected (220 nonhormonal users, and 177 current and 55 previous DMPA users) and 69 HIV‐1–uninfected nonhormonal‐contraceptive users. The mean age was 26.1 years (SD, 4.2) with a median duration of DMPA use among current users of 24.0 months [medians (interquartile range), 12‐48]. A higher proportion of HIV‐1–infected previous (12.7%) or current DMPA users (20.3%) and nonhormonal users (15.0%) had low BMD (Z‐score ≤−2 at any of the three sites) compared with age‐matched HIV‐1–uninfected women (2.9%). HIV‐1 infection and DMPA use were independently associated with significantly lower mean BMD Z‐scores at all sites, with the greatest difference being among HIV‐1–infected current DMPA users (5.6%–8.0%) versus uninfected nonhormonal users. Compared with non‐Hispanic White and Black women, the Ugandan local reference population had generally lower mean BMD at all sites. Newer treatment interventions are needed to mitigate BMD loss in HIV‐1–infected women in resource‐limited settings. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Drugs Causing Bone Loss

Drugs may cause bone loss by lowering sex steroid levels (e.g., aromatase inhibitors in breast cancer, GnRH agonists in prostate cancer, or depot medroxyprogestone acetate - DMPA), interfere with vitamin D levels (liver inducing anti-epileptic drugs), or directly by toxic effects on bone cells (chemotherapy, phenytoin, or thiazolidinedions, which diverts mesenchymal stem cells from forming osteoblasts to forming adipocytes). However, besides effects on the mineralized matrix, interactions with collagen and other parts of the unmineralized matrix may decrease bone biomechanical competence in a manner that may not correlate with bone mineral density (BMD) measured by dual energy absorptiometry (DXA).Some drugs and drug classes may decrease BMD like the thiazolidinediones and consequently increase fracture risk. Other drugs such as glucocorticoids may decrease BMD, and thus increase fracture risk. However, glucocorticoids may also interfere with the unmineralized matrix leading to an increase in fracture risk, not mirrored in BMD changes. Some drugs such as selective serotonin reuptake inhibitors (SSRI), paracetamol, and non-steroidal anti-inflammatory drugs (NSAIDs) may not per se be associated with bone loss, but fracture risk may be increased, possibly stemming from an increased risk of falls stemming from effects on postural balance mediated by effects on the central nervous system or cardiovascular system.This paper performs a systematic review of drugs inducing bone loss or associated with fracture risk. The chapter is organized by the Anatomical Therapeutic Chemical (ATC) classification.