Older Fathers: Epigenetic Factors

 A recent review article published in American Journal of Stem Cells summarized current knowledge of epigenetic factors in fathers.

Epigenetic factors are defined as environmental factors that change the expression of genetics.

We know that as men age, changes in genetic structures have effects on their offspring.

Men who have children after age 40 have higher rates of offspring with:

• schizophrenia
• autism and autism spectrum disorder
• birth defects including heart defects, Down syndrome and other chromosomal anomalies

These effects are not completely understood but do appear to be related to age-dependent methylation of DNA.

Older age is not the only epigenetic influence in fathers. Cigarette smoking, heavy alcohol intake, paternal diet and paternal stress all have some evidence of adversely affecting paternal epigenetic effects.

The effect of advanced paternal age on increased risk in offspring is important as the age at first child is increasing for both men and women. Part of older father effect appears related to the association of older parenthood with increased level of education in the population. (see original chart produced above from U.S. Census Bureau data)

You can read more about this review at MedicalXpress HERE.

Follow the author on Twitter @WRY999 HERE.

Nuts, Booze, Soy and Cardiovascular Mortality

I have previously published several posts related to diet, cardiovascular mortality and cognitive function.  A recent post looked at the relationship of fiber intake and mortality.  Another post examined adherence to a Mediterranean style diet with reduced risk of cognitive decline.  Now there is another important study published examining diet and risk of cardiovascular mortality and all-cause mortality. 

Cardiovascular disease and mortality are important issues for many of the clinical neuroscience diseases.  Heart disease is often the first issue that comes to mind when thinking about cardiovascular disease.  However, here is just a partial list of clinical neuroscience disorders linked to vascular function and health:

• Stroke
• Vascular and Alzheimer's dementia
• Transient ischemic attacks
• Vascular neuropathy

A study Akbaraly et al published in The American Journal of Clinical Nutriton examined dietary history and mortality in those participating in the Whitehall II epidemiologic study.  The Whitehall II study is a study of Londoners who worked in one of 20 civil service occupations.  The baseline data was first collected in 1985 through 1988 (when subjects were 35 to 55 years old) but nutritional information was not collected until 1991-1993.  At that time subjects were scored on a composite index of healthy eating called the Alternative Healthy Eating Index (AHEI) composed of the following subscale categories:

• Vegetables
• Fruits
• Nuts and soy
• Ratio of white meat to red meat
• Total fiber
• Trans fat
• Ratio of unsaturated fats to saturated fats
• Duration of multivitamin use
• Alcohol intake

A composite score is calculated from this index with higher scores indicating presumed healthier diet.  The study subjects were grouped in three groups--low AHEI , intermediate AHEI and high AHEI each group representing a third of the sample.  


After 18 years of follow up, approximately 10% of the low AHEI subjects had died compared to 7% of the high AHEI subjects.  Cardiovascular mortality was 42% less for those in the high AHEI group.  All estimates were made after controlling for a variety of potential confounding sociodemographic variables, i.e. gender, BMI, smoking status).


There were two findings that caught my attention from this study.  One was some of the inflammatory and clinical differences in the groups.  The high AHEI group:

• Had lower serum levels of inflammatory markers C-reactive protein (CRP) and interleukin-6 (IL-6)
• Had lower levels of dyslipidemias (elevated cholesterol or triglycerides)
• Had no lower risk of having hypertension or diabetes

A second finding in the study was the examination of the contribution of individual categories to correlation with lower cardiovascular mortality risk.  Only two of the categories correlated with reduced cardiovascular death rates: nuts and soy AHEI scale score and alcohol intake scale score.  Total fiber intake had the next largest individual contribution but failed to be statistically correlate with reduced mortality.


Maximum scores in the nuts and soy category were reached with only one serving per day.  Maximum scores in the alcohol intake category were reached with two drinks per day for men and one drink per day for women. 


This study adds impetus to further study of what are the most important contributing factors of a "healthy diet" when health is measured as reduce risk of mortality from cardiovascular disease and all other causes.


Photo of Carlos Zambrano pitching for the Chicago Cubs courtesy of Yates Photography.
  
Akbaraly TN, Ferrie JE, Berr C, Brunner EJ, Head J, Marmot MG, Singh-Manoux A, Ritchie K, Shipley MJ, & Kivimaki M (2011). Alternative Healthy Eating Index and mortality over 18 y of follow-up: results from the Whitehall II cohort. The American journal of clinical nutrition, 94 (1), 247-53 PMID: 21613557

Cognitive Decline and the Mediterranean Diet

I have previous posted on some of the research related to beneficial effects of a Mediterranean style diet on health.  In one post I summarized some of the quantities of food types in those judged to have a high rating for the diet.

A recent study by Tangney and colleagues looked at the rate of cognitive decline in a prospective study of elderly adults in Chicago, Illinois.  The study retrospectively judged the diet of participants for characteristics consistent with a Mediterranean diet.  The exact scoring sheet is not included in the manuscript but based on the data provided and other resources, I have attempted to summarize the rating in the spreadsheet below.

Before looking at the rating system, the study results of note include:

• Subjects were rated on compliance with the Mediterranean Diet and another diet rating for compliance with the USDA food pyramid model
• White subjects scored higher on compliance with the Mediterranean diet while black subjects scored higher on the USDA food pyramid model
• Higher scores on the Mediterranean diet were correlated with a slower rate of cognitive decline over time (cognitive decline was judged based on a composite score of a memory test, the Minimental Status Exam and a digit symbol substitution test)

Looking in more detail at this current study, the highest tertile (highest third) in the Mediterranean diet scored 30-45 on the Mediterranean average weekly diet score. (There was some score adjustment for total calorie intake it the study).  The rating includes 11 categories rated from 0-5 on each item for a maximum of 55 points.  The study looked at two different ratings for alcohol intake.  One looked only at alcohol intake and one looked at total alcohol intake. (Use only one of the two rating for item 11, not both).  Both low and high consumption of alcohol is rated lower on the scale than a consumption of 1-2 drinks per day.  Interestingly, a slower rate of cognitive decline was found in the present study when either red wine or total alcohol was used.

The amount of weekly servings for cereals/whole grains and vegetables looks a little overwhelming.  But four slices of whole grain bread per day by itself would put you in the 4 rated for cereals/pasta/whole grains.  You really only need a top score of 5 in 6 categories to reach what was found as the top third in a U.S. sample.  If you throw in a couple of days per week without red meat you can reach a 3 in the red meat category (I hate to make this recommendation since my father raised cattle in Nebraska). 


So looking at the scoring system used in this study helps put the diet in better perspective.  Many people are probably scoring mid-range on the Mediterranean diet but with a few adjustments could significant improve their compliance with the diet.


Photo of WGC Accenture winner Luke Donald at 2010 PGA Championship courtesy of Yates Photography. 


Spreadsheet summary scale adapted from manuscript by author.


Tangney CC, Kwasny MJ, Li H, Wilson RS, Evans DA, & Morris MC (2011). Adherence to a Mediterranean-type dietary pattern and cognitive decline in a community population. The American journal of clinical nutrition, 93 (3), 601-7 PMID: 21177796