Alcoholics who heavily smoke show early signs of brain aging, a new study claims. Researchers looked at the neurocognitive effects of smoking in alcohol dependent (AD) individuals, and found that heavy drinkers who excessively smoke could have more problems with memory, fast and efficient thinking abilities, and problem solving skills. These effects are normally associated with aging individuals, but it's appearing earlier in heavy smokers and drinkers.

"Several factors — nutrition, exercise, comorbid medical conditions such as hypertension and diabetes, psychiatric conditions such as depressive disorders and post-traumatic stress disorder, and genetic predispositions — may also influence cognitive functioning during early abstinence," said Timothy C. Durazzo, co-author and assistant professor in the department of radiology and biomedical imaging at the University of California San Francisco.

Researchers compared memory, attention, learning, and other functions of the brain in 158 participants between the ages 26 and 71. The participants were divided into four groups:

  1. The control group, made up of individuals who had never smoked
  2. nonsmokers who were abstinent for one month and seeking treatment
  3. former smokers who had quit
  4. active smokers

After testing their fine motor skills, general intelligence learning, and working memory, "we found that, at one month of abstinence, actively smoking AD [individuals] had greater-than-normal age effects on measures of learning, memory, processing speed, reasoning and problem-solving, and fine motor skills," Durazzo said. Surprisingly, AD individuals who never smoked, former-smokers, and participants who never smoked had the same level of change as they got older.

"These results indicate the combined effects of these drugs are especially harmful and become even more apparent in older age," said Alecia Dager, associate research scientist in the department of psychiatry at Yale University. "In general, people show cognitive decline in older age. However, it seems that years of combined alcohol and cigarette use exacerbate this process, contributing to an even greater decline in thinking skills in later years."

In the past, researchers were inclined to study smoking's effect on cognitive aging. They found that these consequences of smoking accumulated in the brain over time, so they embarked on a new approach to find consequences in an avid-smoking, heavy drinkers.

"The independent and interactive effects of smoking and other drug use on cognitive functioning among individuals with AD are largely unknown," Dager said. "This is problematic because many heavy drinkers also smoke. Furthermore, in treatment programs for alcoholism, the issue of smoking may be largely ignored."

New findings from this study could produce efficient treatment options for ADs who smoke excessively. These individuals have a hard time remembering and even more difficult time holding onto treatment strategies. Effective interventions could also help improve their thinking skills.The compounding impacts of chronic cigarette smoking, too much alcohol consumption, and aging are linked to increased oxidative damage to the brain, which is when free radicals and other harmful substances directly impair neurons and other cells in the brain.

Durazzo added that "Chronic smoking, and to a lesser extent, alcohol use disorders are also associated with an increased risk for Alzheimer's disease. So, the combination of these modifiable health risks may place an individual at even greater risk for development of Alzheimer's disease."

According to the Centers for Disease Control and Prevention, cigarette smoking causes at least 440,000 deaths every year in the United States.

Results of this study will be published in the October 2013 issue of Alcoholism: Clinical &Experimental Research.