Menopause and Postmenopausal HormoneTherapy¶
Chapter 407 | Part 12: Endocrinology and Metabolism · Part 12 – Endocrinology & Metabolism · Chapter 407
Key Clinical Points¶
- Menopause is defined by 12 months of amenorrhea; average age of onset is 51 years.
- Perimenopause typically lasts 2–8 years (mean 4 years) before the final menses.
- FSH >25 IU/L in a random sample characterizes the late menopause transition.
- Low-dose combined oral contraceptives are a mainstay for perimenopausal symptoms and cycle regularity.
- Transdermal estrogen is preferred over oral estrogen to reduce thrombotic risk.
- WHI data shows significant benefits for vasomotor symptoms (65–90% reduction) and osteoporosis.
- Long-term estrogen-progestin use (≥5 years) increases breast cancer risk by 24%.
- The 'Timing Hypothesis' suggests HT initiated within 3–4 years of menopause may reduce CHD risk.
- Nonhormonal options for vasomotor symptoms include SSRIs, gabapentin, and fezolinetant.
- Osteoporosis management includes bisphosphonates, denosumab, and SERMs.
DEFINITION & CLASSIFICATION¶
• Menopause: Permanent cessation of menstruation due to loss of ovarian follicular function. • Diagnosis: Retrospectively after 12 months of amenorrhea. • Perimenopause: Period preceding menopause where fertility wanes and cycle irregularity increases; lasts until the first year after cessation of menses. • Duration: Precedes final menses by 2–8 years (mean duration: 4 years). • Impact of Smoking: Accelerates the menopausal transition by 2 years.
Diagnostic Definition¶
Definition (Harrison's 22e): Menopause is the permanent cessation of menstruation due to loss of ovarian follicular function. It is diagnosed retrospectively after 12 months of amenorrhea.
EPIDEMIOLOGY¶
• Average Age: 51 years (U.S. women). • Risk Factors: ◦ Modifiable: Smoking (accelerates transition by 2 years). ◦ Non-modifiable: Age.
ETIOLOGY & PATHOPHYSIOLOGY¶
• Follicular Dynamics: ◦ Decline in ovarian mass and fertility starts after age 35. ◦ Depletion of primary follicles begins before birth and proceeds steadily until menopause. ◦ Perimenopause: Intermenstrual intervals shorten (typically by 3 days) due to accelerated follicular phase. • Hormonal Changes: ◦ Estradiol: Falls markedly during transition. ◦ Estrone: Relatively preserved (due to peripheral aromatization of androgens). ◦ FSH: Increases more than LH due to loss of inhibin and estrogen feedback. ◦ Inhibin B & AMH: Useful for assessing reproductive aging. • Clinical Consequence: ◦ Hyperestrogenic, hypoprogestagenic environment in perimenopause → increased risk of endometrial hyperplasia/carcinoma, uterine polyps, and leiomyoma.
CLINICAL FEATURES¶
• Evidence-Based Symptoms: ◦ Strong evidence: Hot flashes, night sweats, irregular bleeding, vaginal dryness. ◦ Moderate evidence: Sleep disturbances. • Inconclusive Evidence (Not strongly linked to ovarian aging): ◦ Mood swings, depression, impaired memory/concentration, somatic symptoms, urinary incontinence, sexual dysfunction.
Symptom Attribution¶
• High Certainty: Hot flashes, night sweats, irregular bleeding, vaginal dryness. ◦ Moderate Certainty: Sleep disturbances. ◦ Low/Inconclusive Certainty: Mood swings, depression, memory issues, somatic symptoms, urinary incontinence, sexual dysfunction.
DIFFERENTIAL DIAGNOSIS¶
• Clinical Challenge: Distinguishing ovarian senescence from other age-related changes. ◦ Symptoms attributed to menopause: Hot flashes, night sweats, irregular bleeding, vaginal dryness. ◦ Symptoms not strongly linked to ovarian aging: Mood swings, depression, impaired memory/concentration, somatic symptoms, urinary incontinence, sexual dysfunction.
DIAGNOSTIC APPROACH¶
- Clinical Assessment: Evaluate impact of hot flashes/night sweats on sleep and quality of life.
- Hormonal Markers (Supportive Criteria): ◦ FSH: → >25 IU/L in a random sample → characteristic of late menopause transition. → <20 IU/L (Day 3) → Good likelihood of pregnancy. → 20 to <30 IU/L (Day 3) → Fair likelihood of pregnancy. → ≥30 IU/L (Day 3) → Poor likelihood of pregnancy. ◦ Estradiol: Imperfect indicator due to high intraindividual variability. ◦ AMH & Inhibin B: Useful for assessing reproductive aging.
- STRAW+10 Staging System: → Used to categorize ovarian aging based on menstrual cycle (primary) and hormones/follicle count (supportive). → Stage -2: Menopausal transition Early (1–3 years; subtle changes in flow/length). → Stage -1: Menopausal transition Late (2 years; persistent ≥7-day difference in length of consecutive cycles; FSH >25 IU/L). → Stage +1: Postmenopause Early (3–6 years; amenorrhea ≥60 days). → Stage +2: Postmenopause Late (Remaining lifespan; amenorrhea ≥60 days; FSH stabilizes; AMH/Inhibin B very low). ※ Note: Table 1 summarizes WHI data, showing significant risks for Estrogen-Progestin (e.g., ↑98% Pulmonary embolism, ↑87% DVT) and benefits (e.g., ↓65–90% symptoms).
MANAGEMENT & TREATMENT¶
- Perimenopausal Therapy: ◦ Low-dose combined oral contraceptives: 20 μg ethinyl estradiol + 1 mg norethindrone acetate (daily for 21 days). → Benefits: Eliminate vasomotor symptoms, restore cyclicity, protect against ovarian/endometrial cancers, increase bone density. ◦ Progestin-only formulations: 0.35 mg norethindrone daily. ◦ Medroxyprogesterone (Depo-Provera): 150 mg IM every 3 months. ◦ Nonhormonal options: Mefenamic acid (initial 500 mg, then 250 mg qid for 2–3 days) or endometrial ablation.
- Postmenopausal Hormone Therapy (HT): ◦ Estrogen: Highly effective for vasomotor and genitourinary symptoms. ◦ Transdermal estrogen: Preferred to reduce thrombotic risk compared to oral. ◦ Bazedoxifene + conjugated estrogens: Approved for vasomotor symptoms.
- Nonhormonal Management of Vasomotor Symptoms: ◦ Antidepressants: Paroxetine mesylate (7.5 mg/d), Venlafaxine (37.5–75 mg/d), Desvenlafaxine (100 mg/d), Fluoxetine (20–30 mg/d), Sertraline (50–100 mg/d), Citalopram (10–20 mg/d), Escitalopram (10–20 mg/d). ◦ Fezolinetant: 45 mg/d. ◦ Gabapentin: 300 mg nightly (up to 900 mg divided). ◦ Oxybutynin: 2.5–5 mg twice per day.
- Osteoporosis Management: ◦ Bisphosphonates: Alendronate (10 mg/d or 70 mg weekly), Risedronate (5 mg/d or 35 mg weekly), Ibandronate (2.5 mg/d, 150 mg monthly, or 3 mg every 3 months IV), Zoledronic acid (5 mg yearly IV). ◦ Denosumab: 60 mg twice per year SC. ◦ SERM: Raloxifene (60 mg/d). ◦ Parathyroid hormone: Teriparatide (20 μg/d SC). ◦ Lifestyle: Weight-bearing exercise, Calcium (1000–1200 mg/d), Vitamin D (600–1000 IU/d).
- Decision Logic for HT Initiation (Table 2): → Step 1: Assess symptoms (must impact sleep or QoL). → Step 2: Rule out absolute contraindications (Cancer, CVD, Liver disease, Vaginal bleeding). → Step 3: Determine recommendation based on risk profile: ◦ RECOMMEND: Age <60 AND Menopause <10 years ago AND Low risk of breast cancer/CVD. ◦ CONSIDER WITH CAUTION: Age ≥60 OR Menopause >10 years ago OR Moderate risk of breast cancer/CVD. ◦ AVOID: High risk of breast cancer or cardiovascular disease.
COMPLICATIONS & PROGNOSIS¶
• Cardiovascular Outcomes: ◦ Coronary Heart Disease: Probable increase in risk for older women/those many years past menopause. ◦ Stroke: Probable increase in risk (~35% increased risk). ◦ Timing Hypothesis: Estrogen may slow early atherosclerosis but harm advanced lesions. • Cancer Risks: ◦ Breast Cancer: ↑24% risk with long-term estrogen-progestin (≥5 years). ◦ Endometrial Cancer: Risk increases with estrogen alone; ↓33% risk with estrogen-progestin. ◦ Ovarian Cancer: Probable increase with long-term use (≥5 years). • Fracture Risk: ◦ Vertebral fracture: 50–80% lower risk in estrogen users. ◦ Hip fracture: 33% reduction with 5–7 years of therapy. ◦ Other peripheral fractures: 25–30% fewer total fractures.
Age-Dependent Risks¶
• Age 50–59: More favorable benefit-risk profile (RR 0.84 for estrogen alone). ● Age 60–69: Neutral benefit-risk profile (RR 0.99). ● Age 70–79: Less favorable benefit-risk profile (RR 1.17).
Discontinuation of HT¶
• Most risks/benefits dissipate within 5–7 years after stopping. ● Exception - Breast Cancer: Risk persists for estrogen-progestin (RR = 1.28). ● Persistence of Benefit: Hip fracture reduction (RR = 0.81) and endometrial cancer reduction (RR = 0.67) persist.
KEY PEARLS & HIGH-YIELD POINTS¶
• Diagnosis: Requires 12 months of amenorrhea; average age is 51. ● FSH Marker: >25 IU/L indicates late transition. ● Smoking: Accelerates menopause by 2 years. ● WHI Data: Estrogen-progestin increases breast cancer risk (24%) but reduces hip fracture risk (33%). ● Timing Hypothesis: Initiation within 3–4 years of menopause may reduce CHD risk. ● Safety: Transdermal estrogen is safer for thrombosis than oral. ● Non-hormonal: SSRIs and Gabapentin are effective for vasomotor symptoms. ● Osteoporosis: Bisphosphonates and Denosumab are standard treatments.
Reference Tables¶
TABLE 407-1 Benefits and Risks of Postmenopausal Hormone Therapy in the Overall Study Population of Women aged 50–79…¶
Harrison's 22e, p.3144
| OUTCOME | EFFECT | ESTROGEN-PROGESTIN | ESTROGEN ALONE | ||
|---|---|---|---|---|---|
| RELATIVE BENEFIT OR RISK |
ABSOLUTE BENEFIT OR RISKb |
RELATIVE BENEFIT OR RISK |
ABSOLUTE BENEFIT OR RISKb |
||
| Definite Benefits | |||||
| Symptoms of menopause |
Definite improvement | ↓65–90% decreased riskc |
↓65–90% decreased riskc |
||
| Osteoporosis | Definite increase in bone mineral density and decrease in fracture risk |
↓33% decreased risk for hip fracture |
6 fewer cases (11 vs 17) of hip fracture |
↓33% decreased risk for hip fracture |
6 fewer cases (13 vs 19) of hip fracture |
| Definite Risksh | |||||
| Definite increase in risk with estrogen alone (see below for estrogen-progestin) Definite increase in risk Definite increase in risk Definite increase in risk with long-term use (≥5 years) of estrogen-progestin Definite increase in risk |
See below ↑98% increased risk ↑87% increased risk ↑24% increased risk ↑57% increased risk |
See below 9 excess cases (18 vs 9) 11.5 excess cases (25 vs 14) 8.5 excess cases (43 vs 35) 47 excess cases (131 vs 84) |
↑35% increased risk (n.s.) ↑48% increased risk ↓21% decreased risk (n.s.) ↑55% increased risk |
||
| Probable or Uncertain Risks and Benefitsh | |||||
| Coronary heart diseased |
Probable increase in risk among older women and women many years past menopause; possible decrease in risk or no effect in younger or recently menopausal womene |
↑18% increased risk (n.s.) |
6 excess cases (41 vs 35) |
No increase in risk | No difference in risk |
| Myocardial infarction | Significant interaction by age group for estrogen alone, with reduced risk in younger—but not older—women (p for trend by age = .02) |
↑24% increased risk (n.s.) |
6 excess cases (35 vs 29) |
No increase in riske | No difference in riske |
| Stroke | Probable increase in risk | ↑37% increased risk | 9 excess cases (33 vs 24) |
↑35% increased risk | 11 excess cases (45 vs 34) |
| Ovarian cancer | Probable increase in risk with long-term use (≥5 years) |
↑41% increased risk (n.s.) |
1 excess case (5 vs 4) |
Not available | Not available |
| Endometrial cancer | Probable decrease in risk with estrogen- progestin during long-term follow-up (see above for estrogen alone) |
↓33% decreased riskf | 3 fewer cases (7 vs 10) |
See above | See above |
| Urinary incontinence | Probable increase in risk | ↑49% increased risk | 549 excess cases (1661 vs 1112) |
↑61% increased risk | 852 excess cases (2255 vs 1403) |
| Colorectal cancer | Probable decrease in risk with estrogen- progestin; possible increase in risk in older women with estrogen alone (p for trend by age = .02 for estrogen alone) |
↓38% decreased risk | 6.5 fewer cases (10 vs 17) |
No increase or decrease in riske |
No difference in riske |
| Type 2 diabetes | Probable decrease in risk | ↓19% decreased risk | 16 fewer cases (72 vs 88) |
↓14% decreased risk |
21 fewer cases (134 vs 155) |
| Dementia (age ≥65) | Increase in risk in older women (but inconsistent data from observational studies and randomized trials) |
↑101% increased risk | 23 excess cases (46 vs 23) |
↑47% increased risk (n.s.) |
15 excess cases (44 vs 29) |
| Total mortality | Possible increase in risk among older women and women many years past menopause; possible decrease in risk or no effect in younger or recently menopausal women (p for trend by age <.05 for both trials combined) |
No increase in risk | No difference in risk | No increase in riske | No difference in riske |
| Global indexg | Probable increase in risk or no effect among older women and women many years past menopause; possible decrease in risk or no effect in younger or recently menopausal women (p for trend by age = .02 for estrogen alone) |
↑12% increased risk | 20.5 excess cases (189 vs 168) |
No increase in riske | No difference in riske |
TABLE 407-2 Approach to Initiating Menopausal Hormone Therapy for Vasomotor Symptom Management 1. Vasomotor symptom…¶
Harrison's 22e, p.3148
| 1. Vasomotor symptom assessment | ||
|---|---|---|
| Confirm that hot flashes and/or night sweats are adversely affecting sleep, daytime functioning, or quality of life. |
||
| 2. Risk factor assessment | ||
| Confirm that there are no absolute contraindications to menopausal hormone therapy |
||
| Breast, endometrial, or other estrogen-dependent cancer | ||
| Cardiovascular disease (heart disease, stroke, transient ischemic attack) | ||
| Active liver disease | ||
| Undiagnosed vaginal bleeding | ||
| 3. Menopausal hormone therapy initiation | ||
| RECOMMEND | CONSIDER WITH CAUTION |
AVOID |
| Age <60 years and Menopause onset within 10 years and Low risk of breast cancera and cardiovascular diseaseb |
Age ≥60 years • • • • • • • OR • • • • • • • Menopause onset >10 years prior • • • • • • • OR • • • • • • • Moderate risk of breast cancera or cardiovascular diseasea |
High risk of breast cancera or cardiovascular diseaseb • • • • • • • • • OR • • • • • • • • • Age ≥60 years or menopause onset >10 years prior and Moderate risk of breast cancera or cardiovascular diseaseb |