Knee pain can come and go for anyone, but if you find yourself with reoccurring knee pain at night, you should visit your doctor as it’s often the result of a larger issue. “It’s often because they have arthritis, commonly osteoarthritis,” Kim Stearns, MD, an orthopedic surgeon, explained for Cleveland Health Clinic. “People with normal, healthy knees usually don’t get pain at night.” Osteoarthritis is a condition caused by wear and tear of the cartilage, which is the tissue protecting your bones and joints. Other symptoms of  osteoarthritis in the knee may include swelling, feeling of warmth in the joint, and the presence of a creaking or crackly sound when you move your knees, according to WebMD. And for more topics you may want to talk to your doctor about, If You’re Taking This OTC Medicine More Than Twice a Week, See a Doctor. According to Healthline, osteoarthritis is the most common form of arthritis, but that doesn’t mean it doesn’t have serious complications. Since knee osteoarthritis is also more likely to strike during night, this can easily disrupt your sleep, as well as reduce your productivity and cause you to gain weight. Knee osteoarthritis can also progress up to a stage 4 severe case, which would have to be treated by bone realignment surgery or total knee replacement. Additionally, without proper treatment, the pain that arises from this condition can lead to anxiety and depression, according to a 2010 study published in the journal Clinical Rheumatology. And for more up-to-date health news delivered right to your inbox, sign up for our daily newsletter. More than 32.5 million adults in the U.S. have osteoarthritis, according to the Centers for Disease Control and Prevention (CDC). And the knee tends to be one of the most commonly affected areas.ae0fcc31ae342fd3a1346ebb1f342fcb According to WebMD, age is a major risk factor for this condition, with the risk of developing osteoarthritis increasing after the you turn 45, but it can occur in young people, too. Factors that can lead to someone developing osteoarthritis at an earlier age include weight, heredity, being a woman, repetitive stress injuries, athletics, and other illnesses like rheumatoid arthritis or certain metabolic disorders. And for more health issues you may face, If You Drink This, You Could Become Resistant to Antibiotics, Study Says. While osteoarthritis may be the likely culprit for your nightly knee pain, there could be something else behind this time-specific ailment, too. Jasmine Marcus, DPT, a physical therapist and certified strength and conditioning specialist, says it could also be patellar tendonitis, a condition caused by inflammation of your knee’s tendon. The truth is, you’re also more likely to notice knee pain at night for two reasons. According to Marcus, some knee-related conditions, like osteoarthritis or patellar tendonitis, tend to “hurt more when you’re at rest than when you’re moving.” Plus, “when you finally slow down and are less busy, you notice things in your body more,” she explains. “If left untreated, certain conditions might worsen,” Marcus warns, which is why you should always talk to your doctor if you have a recurring knee pain. And for more on the aches to pay attention to, take a look at the 25 Common Pains You Should Never Ignore.