(HealthDay News) -- Having an autoimmune disease means that the body's germ-fighting immune system mistakenly attacks normal cells.

(HealthDay News) -- Patellofemoral pain, commonly called runner's knee, describes a host of conditions that cause a dull pain in the front of the kneecap where it connects to the thighbone.

MONDAY, April 18 (HealthDay News) -- Healthy lifestyle changes can significantly lower elevated levels of triglycerides, a type of blood fat associated with heart disease and other health problems, says an American Heart Association scientific statement released Monday.

MONDAY, April 18 (HealthDay News) -- Gay youths are much less likely to attempt suicide when they live in communities where they feel they have some support, either through gay/lesbian groups at school or simply because more same-sex couples live in the area, new research has found.

SUNDAY, April 17 (HealthDay News) -- New research suggests that the development of insulin resistance and type 2 diabetes may be linked to an immune system reaction gone awry.

MONDAY, April 18 (HealthDay News) -- Rapid weight loss in the days before a wrestling match can increase confusion but has no effect on strength, a new study finds.

MONDAY, April 18 (HealthDay News) -- Given the option, parents considering personal genetic testing to predict their own risks for common conditions are also likely to have their children tested, a new study suggests.

MONDAY, April 18 (HealthDay News) -- Hospitalization of seniors may cause temporary memory loss and difficulty understanding discharge instructions, but many return to normal within a month, a new study says.

MONDAY, April 18 (HealthDay News) -- Patients with do-not-resuscitate (DNR) orders are more likely to suffer complications and die after surgery, even after non-emergency procedures, a new study finds.

MONDAY, April 18 (HealthDay News) -- Most people with a reduced sense of smell -- including those who have lost their ability to smell anything at all -- adjust and learn to cope, researchers say.

MONDAY, April 18 (HealthDay News) -- Hospitals are using a pricey blood-clotting drug in treating people who do not have hemophilia, a rare disorder in which blood does not clot normally -- even though its use in such patients is potentially risky, according to new research.

MONDAY, April 18 (HealthDay News) -- New research finds that older diabetics with better control of their blood sugar face less chance of such diabetes-related complications as heart attacks, amputation and kidney disease.

MONDAY, April 18 (HealthDay News) -- Infection with mononucleosis -- the easily spread virus that's the bane of many college students -- and little exposure to sunlight may combine to boost a person's risk for developing multiple sclerosis, a new study suggests.

MONDAY, April 18 (HealthDay News) -- New research suggests that HIV-infected patients are most likely to stay clear of AIDS longer if they start drug therapy when their immune systems are still relatively strong.

Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:

MONDAY, April 18 (HealthDay News) -- Surgeons who drink to excess the night before they operate are more likely to make errors the next day, even as late as four in the afternoon, according to a novel experiment described in a recent Irish study.

MONDAY, April 18 (HealthDay News) -- With another season of warm-weather sports under way, experts are cautioning that many parents don't take sports injury prevention seriously enough -- that they consider commonplace sprains, bruises and pulled muscles "just part of the game."