麻豆传媒

Long-term cancer survivors tended to live longer if they consumed a Mediterranean diet, analysis of an Italian cohort study found.

With a follow-up of almost 13 years, survivors with high adherence to the diet had a 32% lower risk of all-cause mortality compared to those with poor adherence (HR 0.68, 95% CI 0.46-0.99), reported Marialaura Bonaccio, PhD, of the IRCCS Istituto Neurologico Mediterraneo in Pozzilli, Italy, and colleagues.

"Our findings suggest maintaining or adopting a traditional [Mediterranean diet] even after a cancer diagnosis may be beneficial and, importantly, motivate additional science regarding the development of dietary recommendations specifically targeted for cancer survivors," Bonaccio and colleagues wrote in .

High adherence to the diet -- which has an emphasis on vegetable, fruit, fish, olive oil, and nut intake -- was also associated with lower cardiovascular mortality compared with poor adherence (HR 0.42, 95% CI 0.19-0.93). This finding is particularly relevant, according to the researchers, as cancer patients are considered to be at higher risk of cardiovascular disease because of shared modifiable risk factors and, potentially, molecular mechanisms of disease.

The Mediterranean diet "is abundant in foods that are natural sources of polyphenols, which are bioactive compounds with well-established anti-inflammatory, antioxidant, and antitumor activities that may be relevant not only to cancer onset and progression but also and possibly even more to cardiovascular mortality prevention," said Bonaccio and colleagues.

However, high adherence to the diet was not significantly associated with lower cancer mortality (HR 0.79, 95% CI 0.48-1.26).

"Lack of a significant association with cancer mortality could be due to the different types of cancers included and the multifaceted nature of cancer progression and recurrence," the authors wrote.

Using data from the -- a population-based cohort established from 2005 to 2010 that included 24,325 men and women 35 years or older in Italy -- the authors identified 802 participants with a cancer diagnosis at baseline visit who provided relevant medical records and information on cancer treatment. Dietary intake was assessed using an interviewer-administered semiquantitative food frequency questionnaire.

The study population included 476 women (59%) and 326 men (41%) with a mean age of 63 years. Diet was assessed an average of 8.8 years after diagnosis.

Adherence to a Mediterranean diet was measured on a 9-point scale and divided into three categories -- poor (0-3), average (4-5), or high (6-9). Participants with greater diet adherence tended to have a higher socioeconomic status and were more likely to be physically active than those with poor adherence.

During 12.7 years of follow-up, a total of 248 deaths were recorded, including 59 attributed to cardiovascular causes and 140 from cancer. Analyses adjusted for age, sex, energy intake, education, smoking status, physical activity, and hormone replacement therapy, among other factors.

Each 2-point increment in the Mediterranean diet score was associated with a 16% lower risk of all-cause mortality (HR 0.84, 95% CI 0.71-0.99) and a 31% lower risk of cardiovascular death (HR 0.69, 95% CI 0.49-0.97), the study found.

Bonaccio and colleagues acknowledged the study had several limitations. They pointed out that as an observational study causality can't be inferred. In addition, considering that participants had already survived an average of 9 years at baseline, "survival bias" may have affected the results since those with the most active cancers may have already died.

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