Can Elderly Females with Osteoporosis Stop Fosamax Once Started?
Yes, elderly females with osteoporosis can stop Fosamax (alendronate) after 5 years of treatment, and for many women, this does not significantly increase fracture risk for up to 5 additional years due to the drug's persistent bone effects. 1, 2, 3
Evidence-Based Treatment Duration
The American College of Physicians recommends treating osteoporotic women with alendronate for 5 years, after which a drug holiday should be considered. 2 This recommendation is based on:
- Bisphosphonates accumulate in bone and continue to provide antifracture protection even after discontinuation 4, 3
- The landmark FLEX trial demonstrated that women who stopped alendronate after 5 years maintained bone density levels at or above pretreatment levels and showed no significant increase in nonvertebral fractures compared to those who continued treatment 3
- Most randomized controlled trials evaluated bisphosphonate benefits for 3-5 years, and guidelines suggest interrupting therapy after 5-10 years 2
Risk Stratification for Drug Holidays
Lower-Risk Patients (Can Stop After 5 Years)
- Patients at mild fracture risk can stop treatment after 5 years and remain off therapy as long as bone mineral density remains stable and no fractures occur 4
- These patients showed only a 2.4% decline in total hip BMD and 3.7% decline in spine BMD over 5 years off treatment, but levels remained above baseline 3
Higher-Risk Patients (Consider Continuing Beyond 5 Years)
- Women at very high risk of clinical vertebral fractures may benefit from continuing beyond 5 years 3
- The FLEX trial showed a 55% relative risk reduction in clinically recognized vertebral fractures (2.4% vs 5.3%) for those who continued versus stopped treatment 3
- Higher-risk patients should be treated for 10 years, with drug holidays of no more than 1-2 years, and potentially switching to non-bisphosphonate therapy during the holiday 4
Special Considerations in Elderly Patients
When Stopping is Particularly Appropriate
The American Geriatrics Society specifically recommends considering drug holidays or dose reduction after 5 years of alendronate therapy in elderly patients, as fracture protection may persist for up to 5 years after stopping 1
Key factors supporting discontinuation in elderly patients include:
- Multiple comorbidities and polypharmacy increase risk of drug interactions and adverse effects 5, 1
- Poor adherence due to stringent dosing requirements (fasting, upright position for 30 minutes) 5, 6
- Gastrointestinal conditions like hiatal hernia that may be aggravated by bisphosphonates 5
- Long-term use increases risk of rare but serious adverse effects including atypical femur fractures and osteonecrosis of the jaw 1, 4
Monitoring After Discontinuation
- Bone markers rise gradually after stopping but remain somewhat below pretreatment levels even 5 years later 3
- BMD monitoring during treatment is generally not recommended by the American College of Physicians, but may be warranted if treatment failure is suspected 2
- Ensure adequate calcium (1000-1200 mg/day) and vitamin D (800 IU/day) supplementation continues after stopping alendronate 1, 2
Alternative Strategies for Non-Compliant Patients
For elderly patients with poor compliance, dementia, or oral intolerance, parenteral agents are preferred over continuing oral alendronate: 6
- Intravenous zoledronic acid (annual infusion) or subcutaneous denosumab (every 6 months) eliminate daily dosing requirements and improve adherence 6
- These alternatives are particularly appropriate for patients who cannot follow the stringent administration requirements of oral bisphosphonates 6
Critical Pitfall to Avoid
The most common error is failing to ensure adequate calcium and vitamin D supplementation both during and after alendronate therapy, which can reduce treatment efficacy and increase fracture risk. 1, 2 Proton pump inhibitors and SSRIs, commonly used in elderly patients, further increase fracture risk by decreasing calcium absorption and bone formation 5