Factors influencing obstructive sleep apnea:

• Excess weight: Obesity increases the risk of sleep apnea four fold. Fat deposits around the upper airway may obstruct breathing.
• Neck size: People with thicker necks tend to have narrower airways. For men, the risk increases if neck circumference is 17 inches or larger. In women, the risk increases if neck circumference is 15 inches or more.
• A narrowed airway: You may have inherited a naturally narrow throat. Or, tonsils or adenoids may become enlarged and block the airway, particularly in children with sleep apnea.
• Gender: Men are twice as likely to have sleep apnea. However, women increase their risk if they’re overweight, and their risk also appears to rise after menopause.
• Age: Sleep apnea occurs significantly more often in older adults.
• Family history: If you have family members with sleep apnea, you may be at increased risk.
• Use of alcohol, sedatives or tranquilizers: These substances relax the muscles in your throat.
• Smoking: Smokers are three times more likely to have obstructive sleep apnea than are people who’ve never smoked. Smoking may increase the amount of inflammation and fluid retention in the upper airway. This risk likely drops after you quit smoking.
• Nasal congestion: If you have difficulty breathing through your nose — whether it’s from an anatomical problem or allergies — you’re more likely to develop obstructive sleep apnea.

Risk factors associated with central sleep apnea:

• Age: Middle-aged and older people have a higher risk of central sleep apnea.
• Heart disorders: People with congestive heart failure are more at risk of central sleep apnea.
• Narcotic pain medication use: Opioid medications, especially long-acting ones such as methadone, increase the risk of central sleep apnea.
• Stroke: People who’ve had a stroke are more at risk of central sleep apnea or treatment-emergent central sleep apnea

Complications

Sleep apnea is a serious medical condition and may include:

• Daytime fatigue. The repeated awakenings associated with sleep apnea make normal, restorative sleep impossible, therefore people with sleep apnea often experience severe daytime drowsiness, chronic fatigue and irritability.  Additionally, sleep apnea can make concentrating difficult and falling asleep at work common, as well as falling asleep while watching TV or even when driving. As a result, people with sleep apnea have an increased risk of motor vehicle and workplace accidents. A lack of regular restful sleep can also cause us to feel quick tempered, moody or even depressed. Children and adolescents with sleep apnea may do poorly in school or have behavior problems.
• High blood pressure or heart problems. Sudden drops in blood oxygen levels which occur during sleep apnea increase blood pressure and strain the cardiovascular system. If you have obstructive sleep apnea, your risk of high blood pressure is greater than if you don’t. Obstructive sleep apnea may increase the risk of recurrent heart attack, and abnormal heartbeats, such as atrial fibrillation. Obstructive sleep apnea also increases the risk of stroke. If there’s underlying heart disease, these multiple episodes of low blood oxygen (hypoxia or hypoxemia) can lead to sudden death from an irregular heartbeat.
• Type 2 diabetes. People with sleep apnea are more likely to develop insulin resistance and type 2 diabetes compared with people without the sleep disorder.
• Metabolic syndrome. This disorder is a collection of other risk factors linked to a higher risk of heart disease. The conditions that make up metabolic syndrome include high blood pressure, abnormal cholesterol, high blood sugar and an increased waist circumference.
• Complications with medications and surgery. Obstructive sleep apnea is also a concern with certain medications and general anesthesia. People with sleep apnea may be more likely to experience complications following major surgery because they’re prone to breathing problems, especially when sedated and lying on their backs. Before you have surgery, tell your doctor that you have sleep apnea and how it’s treated.
• Liver problems. People with sleep apnea are more likely to have abnormal results on liver function tests, and their livers are more likely to show signs of scarring. This is a condition known as nonalcoholic fatty liver disease.
• Sleep-deprived partners. Loud snoring can keep those around you from getting good rest and eventually disrupt your relationships. It’s not uncommon for a partner to go to another room, or even on another floor of the house, to be able to sleep. Many bed partners of people who snore may be sleep-deprived as well.