How Genes Influence The Risk Of Atopic Dermatitis?

What is Atopic Dermatitis?

Atopic Dermatitis (AD) is a chronic inflammatory condition that makes skin itchy, swollen, and red. In the US, about 16.5 million adults and 9.6 million children have AD.

AD is also called atopic eczema. In children, it usually first appears between ages 3 to 6 months. About 90% of people with AD start showing the symptoms before five years of age.

In people with AD, the immune system starts attacking the healthy skin cells, causing excessive dryness and itching. There are many contributors to AD - genetic, environmental, and stress-related.

For infants and young children, the whole body gets affected by AD. As children get older, dryness and itch are noticed on the elbows and the insides of the knees. For adults, the signs are mostly seen in the hands and feet.

What Causes AD?

AD is not a contagious disease, and thus it does not spread on contact. Doctors believe that there are more numbers of inflammatory cells in the skin of people with AD. AD individuals have a weaker skin barrier than normal people, and this makes their skin very sensitive.

Excessive dryness in the skin allows the entry of allergens and irritants into the skin’s surface, and this can also cause AD.

Here are some of the common triggers that make atopic dermatitis worse in those already living with the condition.
- Hot showers
- Long showers
- Living in dry and cold climates
- Using harsh chemical products on the skin
- Exposure to fabrics like wool and cheap synthetics
- Excessive workouts
- Stress

Commonly Observed Signs Of AD

Scaly patches on the skin
Darker and lighter spots on the skin
Discolored skin
Skin turning leathery
Extreme dryness
Itchy skin
Redness in skin
Rashes on the hands, feet, and face (especially around the eyes)

Is Atopic Dermatitis Genetic?

FLG Gene and AD Risk

Filaggrin is important for the structure of the skin’s outermost layer, the epidermis. It also helps improve the skin’s barrier. Filaggrin is important in locking moisture in the skin and keeping it hydrated.

About 30% of people with atopic dermatitis have a lowered production of filaggrin.

The FLG gene produces profilaggrin, which in turn produces filaggrin. Changes in the FLG gene can cause lowered filaggrin production, which increases the risk of AD.

Abnormal changes or mutations in the FLG gene cause an increased risk for AD.

The A allele of the rs61816761 SNP and the C allele rs12144049 SNP of the FLG gene cause an increased risk of developing Ichthyosis Vulgaris. This condition causes dry and scaly skin and is associated with AD too.

CARD11 Gene and AD Risk

The CARD11 gene helps make proteins involved in the healthy functioning of the immune system, especially in the functioning of the T and B cells. The G allele of rs4722404 increases the chances of developing atopic dermatitis.

Non-genetic Influences On AD Risk

Location: People living in places with low humidity and extremely cold winters are more prone to developing atopic dermatitis.
Asthma and allergic rhinitis (hay fever): People with conditions like asthma are hay fever seem to be at a higher risk for developing atopic dermatitis. The reverse relationship also appears to be true.
Limited exposure to microorganisms in childhood: Modern-day infants and children are more protected from all kinds of microorganisms. This also includes limited exposure to microorganisms like helminth and gut flora that are actually important in developing a stronger immune system. This condition is called the hygiene hypothesis and could be a possible reason for increasing AD in children.
Stress: While stress does not cause AD, it certainly aggravates the symptoms and makes it difficult to manage the itch and inflammation.

The Effects of AD

Moderate cases of AD may not lead to any obvious effects on health. Severe cases may result in the following:
- Extreme itching leading to skin breakouts that lead to sores and cracks
- Pus formation on the skin’s surface
- Increased risk of skin infections
- Inability to sleep because of constant itching
- Development of skin cysts/knots
- Liquid oozing from the skin’s surface
- Psychological issues including depression, anxiety, and feeling of isolation.

Recommendations To Manage/Prevent AD

Keep your skin moisturized: Moisturization is vital to keep the AD symptoms from flaring up. Pick up effective moisturizers and use them twice a day.
Avoid hot water showers: It is recommended that people with AD don’t take hot water showers. Short warm showers are preferable when the weather is cold.
Limit your bathing time: Get out of the shower in 5-10 minutes. Prolonged showers can flare up the symptoms of AD.
Try a bleach bath: Adding a small amount of bleach in your bathtub can help relieve the symptoms of atopic dermatitis.
Use natural/sensitive laundry detergents: Switch over to natural detergents or those designed for sensitive skin.
Wash new clothes before using them: Make sure you pre-wash new clothes before letting them touch the skin.
Eat healthy and fresh food: People consuming more vegetables, fruits, and healthy grains have decreased symptoms of atopic dermatitis.
Similarly, those who consume excessive fast food had increased symptoms of AD.
Bring down your body weight: Increased body weight during childhood increases the risk of developing AD. Stay within healthy BMI levels.

Summary

Atopic dermatitis (AD) is an inflammatory condition that affects the skin.
AD causes itching, redness in the skin, skin breakouts, excessive dryness, and pain. In the United States, one in every ten adults has atopic dermatitis.
90% of the cases of atopic dermatitis are diagnosed within five years of age. AD is a result of more inflammatory cells in the skin and a lowered skin barrier.
The FLG and CARD11 genes are amongst the biggest genetic contributors to AD. Certain SNPs in these genes have been associated with the increased risk of developing AD.
Other causes of atopic dermatitis are low humid climates, obesity, conditions like hay fever and asthma, and lowered exposure to good microorganisms in childhood.
Keeping the skin moisturized, preventing hot water showers, using mild laundry detergents, eating healthy and fresh food, and maintaining healthy BMI levels all help keep the condition manageable.