According to Fitch Ratings, volatile commodity prices are weighing heavily on some U.S. companies even as others enjoy stable industry fundamentals. Fitch said it also believes international growth challenges could create additional pressure.

Fitch noted that among rated U.S. corporates, 26 out of 34 sectors have stable sector outlooks. Of the six sectors with negative outlooks, four are in commodities-related areas: oil & gas, oilfield services, midstream services, and mining. These industries also have negative rating outlooks.

Fitch said many high-yield companies in the oil and gas sector are in survival mode, suffering from some combination of a higher cost base, declining hedge coverage and lack of financeable assets.