Rapid Weight Gain After a Breast Cancer Diagnosis: Patients and Doctors Should Pay Attention

Breast cancer patients’ rapid weight gain after diagnosis may be a bigger problem than previously thought, and doctors need to provide more help to their patients with this issue.

Because weight gain after breast cancer can lead to poorer outcomes, efforts to prevent and manage it should be prioritized and intensified, especially during the first year after diagnosis.

Two-thirds of the patients with breast cancer who responded to the survey were found to be overweight or obese.

This Australian study was published online on February 20 in BMC Cancer. The 60-item online questionnaire was sent to 1835 patients.

Although the online survey response rate was only 15%, most women reported a "high" level of anxiety (worry) about weight gain—and with good reason. The results showed that 64% of women gained an average of 9 kg, and 17% gained more than 20 kg.

In the 2 years following a breast cancer diagnosis, the proportion who were overweight or obese increased from 48% to 67%. Obesity alone almost doubled, rising from 17% to 32%!

- Related Topic: The Link Between Obesity and Cancer: How Does Obesity Cause Cancer?

The researchers note that overweight and obesity are strongly implicated in the development of breast cancer. Weight gain after diagnosis is associated with morbidity (illness) and all-cause mortality (death), and may increase the risk of breast cancer recurrence by 30% to 40%.

The First 1 Year After Diagnosis Is Critical

For 77% of women, weight gain occurred during the 12-18 months after diagnosis. This period may provide a "window of opportunity" for intervention.

Timing is critical for preventing weight gain after a breast cancer diagnosis. Oncologists should therefore discuss the issue early and refer patients to dietitians experienced in oncology. All women should also exercise regularly after a breast cancer diagnosis. Prescribing a Healthy Lifestyle Is as Important as Prescribing Medication.

Women with breast cancer receiving neoadjuvant (preoperative tumor-shrinking) and adjuvant (postoperative protective) treatment are at particularly high risk of gaining weight.

As doctors, we need to think actively about weight, nutrition and exercise and advise on possible interventions. Among patients with breast cancer, weight gain contributes to self-esteem problems and increases the risk of cardiovascular disease and secondary cancers. Several reports suggest that it may worsen prognosis (the course of the disease) and also increase the risk of lymphedema.

As Doctors, We Need to Think Actively About Weight, Nutrition and Exercise

Knowing that obesity is a risk factor for poorer breast cancer outcomes, we should not focus only on treating the breast while neglecting a holistic assessment of the person.

Survey Details

For 277 participants, representing 15% of those invited to the survey, pre- and postdiagnosis body mass index (BMI) data were collected.

Of these women, 254 were diagnosed with stage I–III breast cancer; 33 were diagnosed with ductal carcinoma in situ (DCIS). The median patient age was 59.

The findings showed that:

• 20% of women were of normal weight at diagnosis (BMI <25) but later became overweight (BMI >25),
• 4.8% initially had a BMI of 25-30, meaning they were overweight, but later exceeded 30 and became obese, and
• 60.7% had a BMI increase of >1 kg/m2.
• By contrast, only a small proportion lost weight: about 6% experienced a reduction of more than one BMI category.

Weight gain occurred in 87% of women during the first 2 years after diagnosis and in 58% during the first 12 months. Among those who gained more than 10 kilograms, 78% reported great concern, as did 59% of those who gained more than 5 kilograms.

Across all age groups (35-74 years), 69% of patients gained an additional 0.48 kg per year compared with age-matched controls without a breast cancer diagnosis. Over 5 years, this resulted in an additional 2 kg of weight gain among women with breast cancer.

Conclusion

Women receiving chemotherapy for breast cancer may not feel they have enough energy to exercise and may find eating comforting. Cortisone-derived medicines given to reduce chemotherapy side effects also increase appetite, especially for carbohydrates. The tendency of women receiving treatment for early-stage breast cancer to gain weight should therefore be recognized, highlighted in patient education, and addressed through early referral to a dietitian.